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ZeroUtil Editorial Team

Tools & Documentation

The ZeroUtil Editorial Team builds and maintains a privacy-first alternative to the sea of ad-heavy tool sites. We design and build every utility in the catalog, with a hard rule that client-side tools run entirely in the browser: no uploads, no accounts, and no tracking beyond basic usage analytics. Our background is in full-stack web engineering, with a focus on fast, minimal interfaces and correct, well-tested logic behind each calculator, converter, and generator. We review the tool pages for accuracy and keep the explanations practical, writing the kind of documentation we wished existed when we first reached for these tools. When a utility has to process larger media files it runs on a small server that deletes the files shortly after, and that trade-off is always stated on the page.

How we work

Every tool page and article on ZeroUtil goes through the same four steps before it is published. There is no syndicated content, no rewritten competitor copy, and no page that ships without someone having used the tool it documents.

  1. We build the tool first, then write about it

    The explanation is written against a working implementation, not the other way round. That is why the pages describe edge cases most tool sites skip - what happens to a hyphenated word in a word count, why a QR code with high error correction gets physically denser, where a percentage calculation stops being commutative. Those details come out of building the thing.

  2. Claims are checked against primary sources

    Where a page states a standard, a limit, or an algorithm, it cites the specification or the vendor documentation rather than a secondary blog post. Those citations are stored with the page and rendered on it, so you can check the source without leaving the article. RFCs, W3C and WCAG documents, IRS and other regulator publications, and platform docs are the sources we treat as authoritative.

  3. Numbers are recomputed, not copied

    Tax brackets, character limits, contrast ratios and similar figures are re-derived from the current source at review time. When a figure is year-bound we say which year it applies to on the page, because a silently stale number is worse than no number.

  4. Pages are re-reviewed on a schedule

    Published pages carry a review date and are revisited rather than left to rot. When a standard changes, a platform limit moves, or a browser API we depend on ships or breaks, the affected pages are updated and the review date moves with the change.

The full rules we hold ourselves to are written down: our methodology covers how tools are built and tested, our editorial guidelines covers sourcing, corrections, and the line between explanation and promotion.

What we do and do not cover

We write about the things we build: text and data formats, encoding and hashing, browser APIs, PDFs and images, colour and accessibility, everyday finance and date maths. We do not publish medical, legal, or individual financial advice, and calculators that touch those areas say plainly what they can and cannot tell you. Where a tool is a rough guide rather than an authority - a sleep-cycle estimate, a tax-bracket figure - the page says so.

Corrections

If a page is wrong, we would rather hear it than not. Corrections are made on the page itself with the review date updated, not quietly removed. Reach us via the contact page .

Articles by ZeroUtil Editorial Team

Title card on a dark grid. Kicker GAMING TOOLS, headline WHAT A CROSSHAIR CODE CHANGES, and the line: it writes 21 cl_crosshair lines and leaves the rest alone. A panel shows a block of 21 small amber marks above a dashed divider, with a few grey marks set apart below it.
Gaming Tools

What Importing a CS2 Crosshair Code Actually Changes

A crosshair share code writes 21 cl_crosshair variables, truncates a few, and never touches your scoped or observer crosshair. Why an imported crosshair can still look off.

Title card on a dark grid. Kicker GAMING TOOLS, headline ONE ACCOUNT NUMBER, FOUR STEAMID FORMATS, and the line: SteamID64, STEAM_0 and SteamID3 all read the same 32 bits. A panel shows a small four-segment bit bar and the formula BASE plus accountID, with accountID in amber.
Gaming Tools

SteamID64, STEAM_0 and SteamID3 Share One Account Number

STEAM_0:Y:Z, SteamID3 and SteamID64 all read from the same 32-bit account number. Where Valve's 64-bit layout comes from, and the one thing it cannot derive: a vanity URL.

Title card on a dark grid. Kicker GAMING TOOLS, headline CONVERTING SENSITIVITY BETWEEN GAMES, and the line: the whole method is one division. A panel shows the fraction sens x 0.022 over 0.07 with the two constants in amber, above two turn-circle arcs of different length.
Gaming Tools

Converting Mouse Sensitivity Between Games Is One Division

Every cross-game sensitivity converter runs on one division and seven numbers. Where those numbers come from, and four places the arithmetic stops matching how aim feels.

Article title card. Five grey bars in a row above an amber crosshair drawn as four bars and a centre dot, with the line: 25 characters, 18 bytes, 21 commands
Gaming Tools

CS2 Crosshair Share Codes: What Those 25 Characters Hold

Twenty-five characters hold eighteen bytes, twenty-one console commands, and forty-one bits that carry nothing at all. Every field, decoded and measured.

Article title card. Two columns of five dots either side of a dashed dividing line, the left column amber and the right grey, with the line: the server decides who was recorded
Gaming Tools

How to Hear the Enemy Team's Voice in a CS2 Demo

Whether you can hear the enemy in a CS2 demo depends on what the server recorded, not on your console. Which demos carry it, and the mask for one side.

Article title card. A pair of curly braces containing an amber double slash, with the line: the extension is not the format
Developer Tools

Why tsconfig.json Allows Comments and package.json Does Not

Both files end in .json. One accepts comments and trailing commas, the other throws. The difference is not the extension - it is which parser reads the file.

Article title card. Two outlined rectangles of the same size offset slightly from each other, one grey and one amber, with the line: the drift you cannot see by eye
CSS & Design

How to Compare a Design to Your Build, Pixel by Pixel

Overlay the mockup on the live page and let difference blending find the drift. The method, what each blend mode is for, and what the tools in this category actually cost.

Article title card. Three stacked pages with the topmost in amber, with the line: six operations, one order
PDF Tools

The PDF Tools Everyone Should Know

A hands-on walkthrough of the PDF tasks you hit every week: compress, merge, split, convert, OCR, and sign, with steps you can follow right now.

Article title card. A loudspeaker icon struck through by a thick amber line, with the line: the demo has no voice in it
Gaming Tools

Why You Can't Hear Voice in Your CS2 Demo (Fixes)

Can't hear voice comms in a CS2 or FACEIT demo? The real reasons - no voice in MM/Premier demos, unset tv_listen_voice_indices, commands resetting - and the fixes.

Article title card. A row of five binary digits, three of them picked out in amber, with the sum 13 below, and the line: the slots you pick add up to one number
Gaming Tools

How to Hear Voice Comms in a CS2 Demo

Hear voice comms in any CS2 demo with tv_listen_voice_indices: which demos record voice, how the slot bitmask works, and how to aim it at one player or a whole side.

Article title card. A loudspeaker icon with three arcs beside it, the innermost in amber, with the line: the file with the voice in it is the .dem.zst
Gaming Tools Guide

How to Hear Voice Comms in a FACEIT Demo (CS2)

FACEIT records both teams' voice, but only into one of the two demos a match leaves you. Which file to open, the three commands FACEIT publishes, and how the slot bitmask works.

Article title card. Two pairs of boxes, the upper joined by a single amber arrow and the lower by arrows in both directions, with the line: one of these has no way back
Security & Privacy

Hashing vs Encryption vs Encoding: What People Keep Confusing

Three transformations that all produce gibberish and solve different problems, with the measured cost of picking the wrong one for passwords.

Article title card. Six small grey dots standing for a typed password beside a set of amber concentric rings, with the line: nothing to type, nothing to steal
Security & Privacy

Passkeys vs Passwords: How WebAuthn Actually Replaces the Password

How passkeys, FIDO2 and WebAuthn actually work, why origin scoping ends phishing, and the tradeoffs around recovery and syncing that still bite.

Article title card. Two rows of small blocks, the upper scattered with amber at random and the lower shaded in order, with the line: random, or sorted by time
Developer Tools

UUID vs ULID vs NanoID: Picking an ID Scheme in 2026

UUIDv4, UUIDv7, ULID and NanoID compared on sortability, index behaviour, size and computed collision odds, with a decision guide.

Article title card. A grey dot on a white circle beside a grey dot on a near-black circle, with the line: the formula scores these the same
CSS & Design

WCAG 2.2 Color Contrast: Hitting AA Without Guessing

The AA and AAA thresholds, the luminance maths behind them, the two pairs the formula scores identically and reads differently, and what APCA changes.

Article title card. Two rows of cipher blocks on a dark grid, the lower row ending in an amber block labelled tag, with the line: one mode authenticates, one does not
Security & Privacy

AES-GCM vs AES-CBC: Which Mode to Use and Why

What block cipher modes do, why GCM replaced CBC for new code, what nonce reuse actually leaks, and the NIST limits that make it a requirement rather than advice.

Article title card. Four grey bars standing in for lines of text above a progress bar filled part way in amber, with the line: a score, not a verdict
Text Tools

Flesch-Kincaid Explained: What the Score Means and How to Use It

How the two Flesch formulas are computed, why two syllable counters give different grades for the same text, and what Google actually does with readability.

Overhead view of a person working through a pile of paper receipts and bills with a pocket calculator
Math & Calculators

How to Calculate a Sale Discount: Formulas, Examples, and Common Traps

Percent off, stacked discounts, coupon order, tax order, and why a 100 percent markup followed by 50 percent off leaves the shop at break-even.

Article title card. A stepped line falling and rising like sleep stages through a night, ending at an amber dot, with the line: the cycle is an average, not a timetable
Home & Lifestyle

The 90-Minute Sleep Cycle Rule: What It Actually Means

Where the 90-minute figure comes from, why the cycles are not interchangeable, what sleep inertia really costs, and how much a wearable can honestly tell you.

A row of wooden blocks spelling TAX standing on rising stacks of coins, with a pen, a calculator and a printed chart on the desk around them
Finance Tools

How US Federal Tax Brackets Work

Marginal versus effective rates, why a raise can never cost you money, and the 2026 thresholds worked through line by line.

Article title card. A large pair of amber curly braces, with the line: one format, three dialects
Developer Tools Guide

The Developer's JSON Guide: Everything Worth Knowing in 2026

The spec, the dialects that disagree, the numbers that quietly break, and the security advice that points at the wrong recursion. With the cluster map.

Article title card. A shield with its right half filled in amber, with the line: what leaves the machine, and when
Security & Privacy Guide

Online Privacy Guide: Threat Models for Browser-Based Work

Threat models worth naming, the thirty-second check that beats any privacy policy, and an honest list of which of our own tools upload your file.

A hand holding a phone whose camera is framing a QR code, with a printed restaurant menu on the table behind it
QR & Barcode

How QR Codes Actually Work: A Practical Guide

What the squares mean, what error correction costs in millimetres, why upper case makes a smaller code, and the reasons a printed QR fails to scan.

Article title card. A clock face with amber hands above the digits 1780000000, with the line: one instant, many wall clocks
Date & Time

Unix Timestamps and Timezones: The Confusion That Eats Your Week

What a Unix timestamp is, why the same date string parses two different ways, the two hours DST breaks every year, and what Temporal changes.

Article title card. A dashed straight line and a rising amber curve pulling away from it on a pair of axes, with the line: the gap is the whole point
Finance Tools

Compound Interest, Explained Like You Actually Have to Use It

The arithmetic behind compounding, where the Rule of 72 stops being accurate, and why the early years matter through contributions rather than magic.

A pink sticky note handwritten with the word password and the digits 123456, stuck to a black laptop keyboard against a blue background
Security & Privacy

Password Strength: What Length and Character Sets Buy You

Entropy done honestly, NIST's current 15-character floor, and measured GPU cracking speeds showing the hash function matters more than the extra characters.

Article title card. A clipboard holding three lines of text with an amber exclamation mark on its corner, with the line: paste is a transfer, not a view
Security & Privacy

Never Paste This Into a Random Online Tool

A working threat model for web tools at work: where a paste actually lands, which data is fine, and the thirty-second check that beats reading a privacy policy.

Article title card. Three grey squares and an arrow leading to four narrower amber bars, with the line: 3 bytes become 4 characters
Developer Tools

Base64 Explained: What It Is, Why It Exists, and When Not to Use It

What Base64 does to your bytes, the three variants that produce most decode failures, and the places it still earns its keep.

Article title card. Three segments in a row, the last one amber and labelled sig, with the line: the third part is the only one that matters
Security & Privacy

JWT Authentication Mistakes That Keep Appearing in Production

Algorithm confusion, weak secrets, missing expiry, and the library defaults that quietly changed underneath all the advice written about them.

Article title card. A browser window holding an amber document with a padlock on it, with the line: the file never leaves the tab
PDF Tools

Why Your PDF Tool Should Run in the Browser, Not the Cloud

What an upload actually exposes, which PDF operations a browser can genuinely perform, and which ones cannot run locally at all. Including ours.

Article title card. A pair of large curly braces with an amber warning marker dropped between them, with the line: the parser knows where it broke
Developer Tools

Debugging Malformed JSON: A Field Guide

The parse error is better than its reputation. How to read what V8 says now, the five failure modes behind most broken payloads, and the two errors that hide their position.

Article title card. A large grey square, an arrow, and a much smaller amber square, with the line: same picture, fewer bytes
Image Tools

Client-Side Image Compression: What Happens in the Browser

The real pipeline behind Canvas, OffscreenCanvas and WebCodecs, which formats a browser will and will not encode, and when you still need a server.

The words JSON, JSONC and JSON5 stacked in large white type on a dark background, framed by a pair of oversized curly braces
Developer Tools

JSON vs JSON5 vs JSONC: What Each Parser Actually Accepts

Three formats, one file extension, and no agreement on what counts as valid. Measured against the real parsers, including two that disagree while being the same library.

Two stacks of white blocks printed with percent signs on a wooden table, one topped with a blue block and the other with a red one
Math & Calculators

Percentage Points vs Percent: 5 Mistakes That Change the Answer

A rate that falls 1% and a rate that falls 1 percentage point are ten times apart. That confusion, plus four more that quietly turn a correct number into a wrong one.

Two hands holding a phone, with social reaction icons - hearts, thumbs-up and smiling faces - floating above the screen
Text Tools

Social Media Character Limits 2026: What Each Platform Counts

Post limits for X, Bluesky, LinkedIn, Instagram, Threads, Mastodon, TikTok and Facebook in 2026, plus the four different units they use to count them.

Wooden letter tiles on a bright orange surface, a few arranged to spell HELLO and the rest scattered in a loose pile
Text Tools

What Counts as a Word? Why Counters Disagree on One Text

Paste one sentence into three word counters and get three numbers. Here is the algorithm behind each, which one your deadline actually uses, and where they break.

Tools maintained by ZeroUtil Editorial Team

Security & Privacy

AES-256 Encrypt / Decrypt Online - Free, In-Browser

Encrypt and decrypt text with AES-128, AES-192, or AES-256 in GCM, CBC, or CTR mode. PBKDF2 key derivation, entirely in your browser.

 Fun & Utility

Aesthetic Text Generator

Transform text into vaporwave, upside down, small caps, bold, italic, strikethrough, bubble, and square Unicode styles.

 Math & Calculators

Age Calculator

Calculate exact age in years, months and days from a birthdate.

 Developer Tools

AI Token Counter

Count tokens for GPT-4o, Claude, and Gemini models instantly.

 Converters

Angle Converter

Convert between degrees, radians, gradians, turns, arcminutes and arcseconds.

 Math & Calculators

Area & Volume Calculator

Calculate area of 2D shapes and volume of 3D solids.

 Fun & Utility

ASCII Art Generator

Convert text to large block-letter ASCII art. Supports A-Z, 0-9, and basic punctuation.

 CSS & Design

Aspect Ratio Calculator

Calculate and visualize aspect ratios for any dimensions.

 Video & Audio

Audio Converter

Convert audio between MP3, WAV, M4A, OGG and FLAC. Pick bitrate for lossy formats. Files auto-deleted after 15 minutes.

 Video & Audio

Audio Trimmer

Cut a section from MP3, WAV, M4A, OGG or FLAC files. Stream-copy is fast and lossless. Files auto-deleted after 15 minutes.

 Video & Audio

Audio Waveform Generator

Generate a SoundCloud-style waveform image from any audio file. Decoded in your browser, exported as PNG or SVG.

 Home & Lifestyle

Baby Name Generator

Generate random baby names with filters for gender, cultural origin and starting letter.

 QR & Barcode

Barcode Generator

Generate barcodes in CODE128, EAN-13, UPC, CODE39 and more formats.

 QR & Barcode

Barcode Reader

Free online barcode reader — upload an image to scan and decode barcodes. Supports EAN, UPC, Code 128, QR and more.

 Developer Tools

Base64 Encoder & Decoder

Encode UTF-8 text to Base64 online or decode Base64 back to UTF-8 and plain text. Runs in your browser with no upload.

 Image Tools

Base64 to Image Converter

Decode a Base64 string or data URL back into a viewable image and download it as PNG, JPG, WebP or GIF. Runs in your browser.

 Security & Privacy

Basic Auth Header Generator

Create HTTP Basic Authentication headers from a username and password or API token.

 Text Tools

Binary to Text

Convert text to binary and binary back to text.

 CSS & Design

Blob Shape Generator

Generate organic blob shapes as SVG.

 Math & Calculators

BMI Calculator

Calculate your Body Mass Index and find your weight category.

 CSS & Design

Border Radius Generator

Create CSS border-radius with a visual corner editor.

 CSS & Design

CSS Box Shadow Generator

Create CSS box shadows with a visual editor. CSS box-shadow generator, shadow maker and box-shadow builder with live preview, multi-layer support and Material elevation presets.

 Finance Tools

Budget Planner (50/30/20)

Plan your monthly budget using the 50/30/20 rule. Editable percentages with weekly, monthly and annual breakdowns.

 QR & Barcode

Bulk QR Code Generator

Generate multiple QR codes at once from a list of URLs or text.

 Developer Tools

Bulk URL Encode / Decode

Encode or decode many URLs at once. Paste a newline-separated list and the tool processes each line in parallel, preserving order and blank lines.

 Date & Time

Business Days Calculator

Count business days between two dates excluding weekends and custom holidays.

 Math & Calculators

Byte / Bit Converter

Convert between bits, bytes, KB, MB, GB, TB and PB.

 Home & Lifestyle

Calorie Calculator

Calculate BMR and TDEE using the Mifflin-St Jeor equation with weight loss and gain targets.

 Text Tools

Case Converter

Convert text between UPPER, lower, Title, Sentence, camelCase, snake_case and more.

 Text Tools

Character Counter

Count characters with platform-specific limits for Twitter, Instagram and more.

 Developer Tools

chmod Calculator

Calculate and convert Unix file permission modes between octal and symbolic.

 Developer Tools

Code Screenshot

Create beautiful code snippet images with customizable themes.

 Fun & Utility

Coin Flipper

Flip a virtual coin with animation. Track heads/tails counts, percentages, and streaks.

 Fun & Utility

Color Blindness Simulator

Simulate how colors appear with protanopia, deuteranopia, tritanopia, and achromatopsia using color transformation matrices.

 Developer Tools

Color Converter

Convert colors between HEX, RGB, HSL and CMYK formats.

 CSS & Design

Color Palette Generator

Generate harmonious color palettes, Tailwind-style 50-900 scales and design-system tokens from any base hex color. Also a hex color palette generator (Farbpalette Generator auf Deutsch).

 CSS & Design

Color Picker

Pick colors visually and get HEX, RGB, and HSL values.

 Finance Tools

Compound Interest Calculator

Calculate compound interest with customizable principal, rate, time, frequency and optional monthly contributions.

 Converters

Cooking Measurement Converter

Convert between cups, tablespoons, teaspoons, milliliters, fluid ounces and liters.

 Date & Time

Countdown Timer

Set a target date and time, then watch a live countdown showing days, hours, minutes and seconds.

 Productivity

Cover Letter Generator

Generate professional cover letters from a fill-in template with your details and experience.

 Developer Tools

Cron Expression Parser

Parse cron expressions into human-readable schedules with next run times.

 Gaming Tools

CS2 Crosshair Code Decoder

Decode a CSGO-xxxxx crosshair share code into cl_crosshair console commands.

 Gaming Tools

CS2 Sensitivity Converter

Convert mouse sensitivity between CS2, Valorant, Apex and more, with eDPI and cm/360.

 Gaming Tools

CS2 Voice Comms Calculator

Hear specific players in a CS2 or FACEIT demo - upload it to auto-fill players and get the tv_listen_voice_indices commands.

 Security & Privacy

CSP Header Generator

Build Content-Security-Policy headers with a visual form, presets and per-directive configuration.

 CSS & Design

CSS Animation Generator

Create CSS keyframe animations with presets and visual preview. Doubles as an animate-CSS generator and keyframe maker.

 CSS & Design

CSS Clip Path Generator

Create CSS clip-path shapes with visual editing and presets. Clip-path maker and CSS shape generator in one tool.

 CSS & Design

CSS Filter Generator

Create CSS filter effects with blur, brightness, contrast, grayscale and more. Image-filter CSS in one click.

 Developer Tools

CSS Formatter / Minifier

Format, beautify and minify CSS code.

 CSS & Design

CSS Grid Generator

Build CSS Grid layouts visually with live preview. Works as a grid system generator and HTML grid generator.

 CSS & Design

CSS Pattern Generator

Create repeating CSS background patterns with visual presets.

 CSS & Design

CSS Scrollbar Styler

Create custom CSS scrollbar styles with visual controls.

 CSS & Design

CSS Triangle Generator

Create CSS triangle and arrow shapes using the pure-CSS border technique. Triangle generator and path CSS generator in one.

 Developer Tools

CSV to JSON Converter

Convert CSV data to JSON array format.

 Developer Tools

cURL to Code Converter

Convert cURL commands to fetch, Python requests, and more.

 Converters

Data Storage Converter

Convert between bits, bytes, KB, MB, GB, TB and PB with binary (1024) and decimal (1000) modes.

 Date & Time

Date Difference Calculator

Calculate the exact difference between two dates in years, months, days, weeks, hours and minutes.

 Date & Time

Date Formatter

Format any date in 12 patterns including ISO 8601, US, EU, RFC 2822, Unix timestamp and relative.

 Fun & Utility

Decision Wheel

Add custom options and spin a colorful wheel to make random decisions. Animated CSS wheel with smooth deceleration.

 Fun & Utility

Dice Roller

Roll D4, D6, D8, D10, D12, or D20 dice. Choose quantity, see individual results and totals with roll history.

 Developer Tools

Diff Checker

Compare code or text with line-by-line diff and unified output.

 Productivity

Digital Whiteboard

Draw and sketch on an HTML5 canvas with pen, eraser, colors, and PNG download.

 Math & Calculators

Discount Calculator

Calculate discount amount, sale price, savings, and discounted value with optional sales tax. Supports stacked coupons.

 Converters

Electricity Cost Calculator

Calculate daily, monthly and yearly electricity cost from watts, hours per day and electricity rate.

 Productivity

Email Signature Generator

Generate professional HTML email signatures with contact details and social links.

 Text Tools

Emoji Picker & Search

Search and copy emojis by name or category.

 Converters

Energy Converter

Convert between joules, calories, kilocalories, BTU, kilowatt-hours and electronvolts.

 Video & Audio

Extract Audio from Video

Pull the audio track out of MP4, WebM, MOV and MKV. Output as MP3, WAV, AAC or Opus. Files auto-deleted after 15 minutes.

 Text Tools

Fancy Text Generator

Generate stylish text with bubbles, squares, upside down and more for social media.

 Image Tools

Favicon Generator

Generate favicons in all standard sizes (16x16 to 512x512) for websites and PWAs.

 Math & Calculators

Fibonacci Sequence Generator

Generate Fibonacci numbers up to any length.

 Text Tools

Find & Replace

Find and replace text with regex support and case-sensitive options.

 Productivity

Flashcard Maker

Create and study flashcards with front/back content, shuffle, and navigation.

 CSS & Design

Flexbox Playground

Build CSS flexbox layouts visually with live preview and copy-ready CSS output.

 CSS & Design

Font Pair Suggester

Discover beautiful Google Font pairings for your projects.

 Fun & Utility

Fortune Cookie

Open a virtual fortune cookie to reveal a random fortune with lucky numbers. 50+ unique fortunes.

 Math & Calculators

Fraction Calculator

Add, subtract, multiply and divide fractions with simplified results.

 Finance Tools

Freelance Hourly Rate Calculator

Compute the hourly rate a freelancer must charge to hit a target take-home after taxes, business expenses, profit margin and realistic billable utilisation.

 Converters

Fuel Economy Converter

Convert between MPG (US), MPG (UK), L/100km and km/L with inverse relationship handling.

 Math & Calculators

GCD / LCM Calculator

Find the greatest common divisor and least common multiple of two numbers.

 Image Tools

GIF Maker

Turn multiple images into an animated GIF with custom frame delay.

 CSS & Design

Glassmorphism Generator

Create frosted glass CSS effects with backdrop blur. Glassmorphism generator and glass effect CSS builder in one.

 SEO & Web Tools

Google SERP Preview

Preview how your page appears in Google search results with character count indicators.

 Math & Calculators

GPA Calculator

Calculate your weighted GPA on the 4.0 scale from letter grades and credit hours.

 Math & Calculators

Grade Calculator

Work out your weighted course grade and the score you need on the final exam.

 CSS & Design

Gradient Generator

Create CSS linear and radial gradients with a visual editor.

 Productivity

Grammar Checker

Check text for double spaces, repeated words, misspellings, capitalization, and passive voice.

 Developer Tools

Hash Generator

Generate SHA-1, SHA-256, SHA-384 and SHA-512 hashes from text.

 SEO & Web Tools

Heading Structure Analyzer

Extract and visualize H1-H6 heading hierarchy with SEO issue detection.

 Developer Tools

HMAC Generator

Generate HMAC signatures with SHA-1, SHA-256, SHA-384 and SHA-512.

 Date & Time

Hours Calculator

Count hours and minutes between two times, with breaks, overnight shifts, and decimal hours.

 SEO & Web Tools

Hreflang Tag Generator

Generate hreflang link tags for multilingual websites with x-default support.

 Developer Tools

HTML Entity Encode / Decode

Encode special characters to HTML entities or decode them back.

 Developer Tools

HTML Formatter / Beautifier

Format, beautify and minify HTML code.

 Developer Tools

HTML to JSX Converter

Convert HTML to JSX with automatic attribute conversion.

 Text Tools

HTML to Markdown

Convert HTML to clean Markdown text.

 Developer Tools

HTTP Status Code Reference

Searchable reference for all HTTP status codes with descriptions.

 Image Tools

Image Blur & Pixelate

Apply blur or pixelation effects to images with adjustable intensity.

 Image Tools

Image Color Picker

Upload an image and pick colors in HEX, RGB, and HSL with a visual color history.

 Image Tools

Image Compressor

Compress images by adjusting quality to reduce file size without losing visual clarity.

 Image Tools

Image Cropper

Crop images with preset aspect ratios like 1:1, 16:9, and 4:3 using a visual editor.

 Image Tools

Image Flip & Rotate

Flip images horizontally or vertically and rotate by 90, 180, or 270 degrees.

 Image Tools

Image Format Converter

Convert images between PNG, JPEG, and WebP formats in one click.

 Image Tools

Image Metadata Viewer

View file info, dimensions, aspect ratio, and basic EXIF data from any image.

 Image Tools

Image Resizer

Resize images by pixels or percentage with aspect ratio lock.

 Image Tools

Image Resizer (Server-Side)

Resize JPEG, PNG, WebP, AVIF, and HEIC on our EU servers with proper fit modes. Files auto-deleted after 15 minutes.

 Image Tools

Image to ASCII Art

Convert images to ASCII art using text characters with adjustable width and brightness.

 Image Tools

AVIF Converter

Convert JPEG, PNG, WebP, or HEIC to AVIF with a quality slider. Files auto-deleted after 15 minutes.

 Image Tools

Image to Base64 Converter

Convert an image to a Base64 data URL or raw Base64 string for HTML, CSS, and API payloads. Runs in your browser.

 PDF Tools

Image to PDF

Combine multiple JPG and PNG images into a single PDF document.

 Image Tools

Image Vectorizer

Convert PNG, JPG, WebP, GIF or BMP images to scalable SVG vector format directly in your browser.

 Image Tools

Image Watermark

Add customizable text watermarks with controls for size, color, opacity, and position.

 Finance Tools

Inflation Calculator

Calculate the impact of inflation on purchasing power over any time period.

 Finance Tools

ROI Calculator (Return on Investment)

Calculate ROI, CAGR, annual return and percentage gain from initial investment, final value and holding period. Works for stock ROI, after-tax ROI, social ROI and required-return scenarios.

 Text Tools

Invisible Character Detector

Find and remove hidden zero-width and invisible characters from text.

 Productivity

Invoice Generator

Create professional invoices with line items, tax calculation, and printable output.

 Developer Tools

IP Subnet Calculator

Calculate network, broadcast, host range and masks from any IPv4 CIDR.

 Developer Tools

JavaScript Formatter / Minifier

Format, beautify and minify JavaScript code with Prettier-style defaults.

 Developer Tools

JSON Dialect Detector

Tell whether a file is JSON, JSONC or JSON5 - and convert it to strict JSON.

 Developer Tools

JSON Diff Viewer

Compare two JSON documents semantically. Detects added, removed and changed keys and array elements; ignores object key order.

 Developer Tools

JSON Formatter

Format, validate and minify JSON with syntax highlighting.

 Developer Tools

JSON to CSV Converter

Convert JSON arrays to CSV format with custom delimiters.

 Developer Tools

JSON to XML Converter

Convert JSON to XML format instantly in your browser.

 Developer Tools

JSON to YAML Converter

Convert JSON to YAML format instantly.

 Developer Tools

JSONPath Evaluator

Run JSONPath queries against a JSON document and see the matched values. Supports child, index, slice, wildcard and recursive-descent operators.

 Developer Tools

JWT Decoder

Decode and inspect JWT tokens — header, payload and claims.

 Developer Tools

JWT Token Generator

Sign a JWT (HS256, HS384, HS512) from a JSON payload and shared secret. Runs entirely in your browser using the Web Crypto API.

 Developer Tools

Keycode Info

Press any key to inspect its KeyboardEvent properties instantly.

 SEO & Web Tools

Keyword Density Checker

Analyze word frequency with single words, bigrams and trigrams with density percentages.

 Converters

Length Converter

Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards and miles.

 Text Tools

Line Counter

Count total lines, blank lines and get line statistics.

 Math & Calculators

Loan / Mortgage Calculator

Calculate monthly payments, total interest and amortization for any loan.

 Finance Tools

Loan EMI Calculator

Calculate Equated Monthly Installments for any loan. See EMI, total interest and payment breakdown.

 Text Tools

Lorem Ipsum Generator

Generate placeholder text in paragraphs, sentences or words.

 Fun & Utility

Love Calculator

Enter two names and calculate a fun compatibility score from 0-100% with hearts and visual display.

 Developer Tools

Markdown Preview

Write Markdown and see rendered HTML in a live split-pane preview.

 Productivity

Markdown Table Generator

Build a Markdown table interactively. Add rows and columns, set per-column alignment and copy the GitHub-flavoured output.

 Text Tools

Markdown to HTML

Convert Markdown to HTML with live preview.

 Productivity

Meeting Cost Calculator

Calculate the true cost of meetings based on attendees, hourly rates, and duration with a live timer.

 SEO & Web Tools

Meta Tag Generator

Generate complete HTML meta tags including Open Graph and Twitter Card tags.

 Developer Tools

MIME Type Lookup

Look up MIME types by file extension or search by type.

 Text Tools

Morse Code Translator

Translate text to Morse code and Morse code to text.

 Finance Tools

Mortgage Calculator

Estimate monthly mortgage payments, total interest and total cost. Includes full amortization schedule.

 Home & Lifestyle

Moving Box Calculator

Estimate moving boxes needed by room type with breakdown by small, medium and large sizes.

 Video & Audio

Mute Video

Remove the audio track from MP4, WebM, MOV and MKV. Stream-copy keeps the video quality intact. Files auto-deleted after 15 minutes.

 Developer Tools

NDJSON / JSONL Viewer

Parse and inspect NDJSON and JSONL files line by line.

 Finance Tools

Net Worth Calculator

Calculate your net worth by adding assets and liabilities. Dynamic rows with debt-to-asset ratio.

 CSS & Design

Neumorphism Generator

Create soft UI neumorphic shadows and effects.

 Productivity

Notes Scratchpad

Simple persistent notepad with auto-save, word count, and local storage.

 Math & Calculators

Number Base Converter

Convert numbers between binary, octal, decimal and hexadecimal.

 SEO & Web Tools

Open Graph Preview

Preview how your page looks when shared on Facebook and LinkedIn.

 Home & Lifestyle

Paint Calculator

Calculate how many gallons of paint you need for a room based on dimensions, doors and windows.

 Productivity

Paraphrasing Tool

Rewrite text using synonym replacement for basic paraphrasing. No AI required.

 Security & Privacy

Password Entropy Calculator

Estimate password entropy, character pool size and crack-time ranges for online and offline attacks.

 Security & Privacy

Password Generator

Generate cryptographically secure random passwords with configurable length, character types and entropy display.

 Security & Privacy

Password Strength Checker

Check password strength the way NIST SP 800-63B-4 asks for it: guessing difficulty and length, not character variety.

 Finance Tools

Paycheck Calculator

Estimate take-home pay after federal tax, Social Security and Medicare deductions.

 Security & Privacy

PBKDF2 Hash Generator

Derive cryptographic keys from passwords using PBKDF2 with configurable iterations, salt and hash function.

 PDF Tools

PDF Compressor

Compress PDFs with Ghostscript image downsampling. Pick a quality preset. Files auto-deleted after 15 minutes.

 PDF Tools

PDF Merge (Server-Side)

Merge up to 20 PDFs into a single document on our EU servers using qpdf. Files auto-deleted after 15 minutes. Handles large or password-cleared inputs the in-browser merger cannot.

 PDF Tools

PDF Merger

Merge multiple PDF files into a single document with drag-and-drop reordering.

 PDF Tools

PDF Page Reorder

Rearrange pages in a PDF document with a visual drag-and-drop interface.

 PDF Tools

PDF Password Protect

Add AES-256 password protection to PDF files via qpdf. Files auto-deleted after 15 minutes.

 PDF Tools

PDF Rotate (Server-Side)

Rotate every page of a PDF, or just a selected range, by 90, 180, or 270 degrees on our EU servers. qpdf-based, metadata preserved. Auto-deleted after 15 minutes.

 PDF Tools

PDF Rotate Pages

Rotate individual or all pages in a PDF by 90, 180, or 270 degrees.

 PDF Tools

PDF Split (Server-Side)

Split a PDF into multiple files by page ranges on our EU servers. Returns a zip containing one PDF per range. Auto-deleted after 15 minutes. Handles documents the in-browser splitter cannot.

 PDF Tools

PDF Splitter

Extract specific pages or page ranges from a PDF into a new document.

 PDF Tools

PDF to Image

Convert PDF pages to PNG or JPG images with adjustable quality and scale.

 PDF Tools

PDF to Text

Extract text content from PDF documents with word and character counts.

 PDF Tools

PDF Unlock

Remove password protection from a PDF you have the password to. qpdf-based. Files auto-deleted after 15 minutes.

 Math & Calculators

Percentage Calculator

Calculate percentages: X% of Y, percentage increase/decrease, and more.

 Home & Lifestyle

Pet Age Calculator

Convert dog or cat age to human years with breed size adjustment for dogs.

 Image Tools

Placeholder Image Generator

Generate custom placeholder images with configurable size, colors, and text.

 Date & Time

Pomodoro Timer

25-minute work and 5-minute break cycles with progress bar, session counter and phase tracking.

 Converters

Pressure Converter

Convert between pascals, kilopascals, bar, atmospheres, PSI, mmHg and torr.

 Math & Calculators

Prime Number Checker

Check if a number is prime and find all primes up to any limit.

 QR & Barcode

QR Code Generator

Generate QR codes for URLs, text, email, phone and WiFi.

 QR & Barcode

QR Code Reader

Scan and decode QR codes from any image online - upload a photo, screenshot or saved picture and read the QR contents instantly in your browser.

 Fun & Utility

Random Color Generator

Generate random colors with HEX, RGB and HSL values. Random color picker, colour randomizer and 5-color palette builder with history.

 Fun & Utility

Random Name Generator

Generate random first and last names with options for gender, real, fantasy, or business name types.

 Math & Calculators

Random Number Generator

Generate random numbers within a range with options for uniqueness and sorting.

 Fun & Utility

Random Quote Generator

Generate random inspirational, funny, motivational, and wisdom quotes from a curated collection of 50+ quotes.

 Text Tools

Random String Generator

Generate random strings with configurable length and character set.

 SEO & Web Tools

Readability Checker

Free reading level checker and writing grade level analyzer. Flesch-Kincaid, Flesch Reading Ease, Gunning Fog and Coleman-Liau scores in one place.

 Home & Lifestyle

Recipe Scaler

Scale recipe ingredients up or down proportionally for any number of servings.

 Developer Tools

Regex Tester

Test regular expressions with live highlighting, matches and capture groups.

 Text Tools

Remove Duplicate Lines

Remove duplicate lines from text with case-sensitive and sorting options.

 Productivity

Resume Builder

Build a professional resume with sections for experience, education, and skills. Print or download as HTML.

 Finance Tools

Retirement Calculator

Project your retirement fund based on current savings, monthly contributions and expected returns.

 SEO & Web Tools

Robots.txt Generator

Generate robots.txt files with user-agent rules, allow/disallow paths and sitemap.

 Math & Calculators

Roman Numeral Converter

Convert numbers to Roman numerals and Roman numerals to numbers.

 Text Tools

ROT13 Encoder / Decoder

Encode and decode text with ROT13 and other rotation ciphers.

 Security & Privacy

RSA Key Generator

Generate RSA key pairs (2048 or 4096 bit) in PEM format using the Web Crypto API.

 Math & Calculators

Salary / Hourly Rate Calculator

Convert between annual salary, monthly, weekly, daily and hourly pay rates.

 Finance Tools

Salary to Hourly Converter

Convert an annual salary to an hourly wage and back. Hourly, weekly, bi-weekly, monthly and annual figures side by side.

 SEO & Web Tools

Schema Markup Generator (JSON-LD)

Generate JSON-LD structured data for Article, FAQ, Product, Organization, LocalBusiness, HowTo, Recipe and Event.

 SEO & Web Tools

Article Schema Generator (JSON-LD)

Generate Article JSON-LD schema for blog posts, news pages and long-form guides.

 SEO & Web Tools

FAQ Schema Generator (JSON-LD)

Generate FAQPage JSON-LD schema for FAQ sections with Question and Answer nodes.

 SEO & Web Tools

Organization Schema Generator (JSON-LD)

Generate Organization JSON-LD schema with logo, contactPoint and sameAs for knowledge panel signals.

 SEO & Web Tools

Product Schema Generator (JSON-LD)

Generate Product JSON-LD schema with Offer, price, currency and AggregateRating for merchant listings.

 Math & Calculators

Scientific Calculator

Full-featured scientific calculator with trigonometry, logarithms and more.

 Security & Privacy

Secure Token Generator

Generate cryptographically secure random tokens in base64url, hex, alphanumeric or UUID v4 format.

 Security & Privacy

Security Hash Generator

Generate SHA-1, SHA-256, SHA-384 and SHA-512 hashes from text or files using the Web Crypto API.

 SEO & Web Tools

SEO Slug Generator

Generate SEO-friendly URL slugs with stop word removal and length control.

 SEO & Web Tools

SEO Word Counter

Count words, characters, headings, paragraphs with keyword density and reading level.

 Converters

Shoe Size Converter

Convert shoe sizes between US, UK, EU and JP sizing systems for men and women.

 Home & Lifestyle

Sleep Cycle Calculator

Find when to sleep or wake up based on 90-minute REM cycles. Free bedtime and wake time calculator.

 Productivity

Social Media Character Counter

Check character counts against limits for Twitter, Instagram, LinkedIn, Facebook, YouTube, and TikTok.

 Converters

Speed Converter

Convert between km/h, mph, m/s, ft/s and knots.

 Developer Tools

SQL Formatter

Format and beautify SQL queries with keyword uppercasing.

 Math & Calculators

Statistics Calculator

Calculate mean, median, mode, standard deviation, variance and more.

 Gaming Tools

SteamID Converter

Convert between SteamID64, STEAM_0:Y:Z, SteamID3 [U:1:W], account ID and profile URL.

 Date & Time

Stopwatch

Precise online stopwatch with start, stop, reset and lap time recording. Centisecond accuracy.

 Text Tools

String Length Calculator

Calculate string length in characters, bytes (UTF-8/UTF-16) and graphemes.

 Image Tools

EXIF Stripper

Remove EXIF, GPS, camera, software, and XMP metadata from JPEG, PNG, WebP, HEIC. Files auto-deleted after 15 minutes.

 SEO & Web Tools

Structured Data Validator

Validate JSON-LD structured data for correct context, type and required fields.

 Image Tools

SVG to PNG Converter

Convert SVG vector graphics to PNG raster images at any custom size.

 CSS & Design

SVG Wave Generator

Create decorative SVG wave dividers for websites.

 Developer Tools

Tailwind CSS Playground

Write HTML with Tailwind CSS classes and see live results. Use it as an online Tailwind editor and Tailwind play environment.

 Finance Tools

Tax Bracket Calculator

Calculate federal income tax using 2024 and 2025 US tax brackets, with 2023 reference. See effective rate, marginal rate and tax per bracket.

 Converters

Temperature Converter

Convert between Celsius, Fahrenheit and Kelvin with formula display.

 Text Tools

Text Diff / Compare

Compare two texts side by side and highlight the differences.

 Text Tools

Text Repeater

Repeat text multiple times with custom separators.

 Text Tools

Text Reverser

Reverse text by characters, words or lines.

 CSS & Design

Text Shadow Generator

Create CSS text shadows with a visual editor and presets. Doubles as a CSS font shadow generator.

 Text Tools

Text Sorter

Sort lines alphabetically, numerically, by length or randomly.

 Text Tools

Text to Handwriting

Render text as handwritten notes with customizable fonts and paper styles.

 Text Tools

Text to Slug

Generate URL-friendly slugs from any text.

 Home & Lifestyle

Tile Calculator

Calculate tiles needed for floors or walls with grout spacing and waste percentage.

 Converters

Time Unit Converter

Convert between milliseconds, seconds, minutes, hours, days, weeks, months and years.

 Date & Time

Timezone Converter

Convert times between timezones instantly. Supports 28+ world timezones with DST handling.

 Math & Calculators

Tip Calculator

Calculate the tip and split the bill between any number of people. Works as a tip splitter and bill splitter in one.

 Developer Tools

TOML to JSON Converter

Convert TOML configuration to JSON format.

 Security & Privacy

TOTP Generator

Generate time-based one-time passwords (TOTP) from a base32 secret with live 30-second countdown.

 SEO & Web Tools

Twitter Card Preview

Preview how your page looks when shared on Twitter/X with meta tag generation.

 Productivity

Typing Speed Test

Test your typing speed with real-time WPM, accuracy, and character tracking.

 Text Tools

Unicode Text Converter

Convert text to bold, italic, script, fraktur and other Unicode styles.

 Math & Calculators

Unit Converter

Convert length, weight, temperature, speed, volume and area units.

 Converters

All-in-One Unit Converter

Master converter with tabs for length, weight, temperature, speed, area and volume.

 Developer Tools

Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and back.

 Developer Tools

URL Encoder / Decoder

Online URL encoder and decoder for query strings, paths, and HTTP request values - percent-encodes characters with encodeURIComponent.

 Developer Tools

URL Parser

Break a URL into protocol, host, port, path, query parameters and hash with a structural view of every component.

 Developer Tools

User Agent Parser

Parse user agent strings to identify browser, OS and device.

 Developer Tools

UUID Generator

Generate UUID v4 identifiers, single or in bulk.

 Developer Tools

UUID Version Detector

Identify the version (v1, v3, v4, v5, v6, v7, v8) and variant of any UUID and extract embedded timestamps.

 Video & Audio

Video Compressor

Compress MP4, WebM and MOV videos with H.264 to make them smaller for sharing. Files auto-deleted after 15 minutes.

 Video & Audio

Video Concatenator

Join 2 to 10 video clips into a single MP4. Reorder before submit, server-side FFmpeg picks concat-demuxer for matching codecs and re-encode for mixed inputs. Files auto-deleted after 15 minutes.

 Video & Audio

Video Converter

Convert videos between MP4, WebM, MKV, MOV, and extract MP3 audio.

 Video & Audio

Video Cropper

Crop MP4, WebM, MOV and MKV videos to a rectangle or aspect preset (16:9, 9:16, 1:1, 4:3). Server-side FFmpeg, no signup. Files auto-deleted after 15 minutes.

 Video & Audio

Video Reverser

Reverse an MP4, WebM, MOV or MKV video and its audio with one click. Server-side FFmpeg handles the full re-encode. Files auto-deleted after 15 minutes.

 Video & Audio

Video Speed Changer

Speed up or slow down MP4, WebM, MOV and MKV videos from 0.25x to 4x. Audio is re-pitched with FFmpeg's atempo chain so voices stay natural. Files auto-deleted after 15 minutes.

 Video & Audio

Video to GIF Converter

Convert MP4, WebM and MOV videos to animated GIFs. Files are auto-deleted after 15 minutes.

 Video & Audio

Video Trimmer

Cut a section from MP4, WebM or MOV videos. Stream-copy is fast and lossless.

 Video & Audio

Voice Recorder

Record voice memos directly in your browser. The audio never leaves your device - no upload, no signup.

 Home & Lifestyle

Wallpaper Calculator

Calculate wallpaper rolls needed for a room with pattern repeat, square-feet workflow, and metric/imperial conversions.

 Home & Lifestyle

Water Intake Calculator

Calculate daily water intake based on body weight, activity level and climate.

 Date & Time

Week Number Calculator

Find the ISO week number, day of year, days remaining, quarter and more for any date.

 Converters

Weight Converter

Convert between milligrams, grams, kilograms, ounces, pounds, stone and tons.

 Text Tools

Whitespace Remover

Trim, collapse or remove whitespace and blank lines from text.

 QR & Barcode

WiFi QR Code Generator

Generate a QR code for your WiFi network so guests can connect by scanning.

 Text Tools

Word Counter

Count words, characters, sentences, paragraphs and estimate reading time.

 Date & Time

World Clock

Live-updating clocks for multiple timezones. Add and remove cities to build your custom dashboard.

 Developer Tools

XML Formatter / Validator

Format, beautify and validate XML with customizable indentation.

 SEO & Web Tools

XML Sitemap Generator

Generate valid XML sitemaps from a list of URLs with changefreq and priority.

 Developer Tools

YAML to JSON Converter

Convert YAML to JSON format instantly.