Video Cropper

How to crop a video online

1. Drop a video file onto the page. MP4, WebM, MOV and MKV are accepted up to 500 MB. The upload travels over HTTPS to our EU-located processing server.
2. Pick an aspect preset (16:9, 9:16, 1:1, 4:3) or type a custom rectangle. The aspect presets fit the largest rectangle of that ratio inside the source and center it; tweak X and Y to bias the crop left/right or up/down.
3. Switch to Percent mode if you would rather think in percentages of the frame instead of raw pixels. The page converts to integer pixels at submit time.
4. Press Crop video. The job enters the BullMQ queue, FFmpeg runs the crop filter and re-encodes to H.264 + AAC, and a signed download URL appears when the job finishes.
5. Download the cropped clip. Both the source upload and the produced output are auto-deleted from disk within 15 minutes.

What this tool does

This is a free video cropper that cuts a rectangular region out of an MP4, WebM, MOV or MKV file. Cropping is one of the workhorse edits for short-form video: re-framing a horizontal 16:9 source to vertical 9:16 for Reels and TikTok, trimming letterboxed black bars off a downloaded clip, or producing a square 1:1 version for an Instagram feed. We run the operation server-side with FFmpeg so the page does not depend on SharedArrayBuffer or any other cross-origin-isolation feature - which means it works in every modern browser including the most locked-down corporate setups.

Why crop in the browser

An online crop video online tool earns its keep when you do not want to install a desktop editor for one quick reframing. CapCut, Premiere, Final Cut, DaVinci Resolve and iMovie all support cropping but each one is overkill for a 10-second clip. The catch with most online crop services is unclear retention - the same upload might sit on someone else's server indefinitely. Our retention policy is strict and automatic:

• Files are processed on EU servers and auto-deleted within 15 minutes of upload.
• The signed download URL expires alongside the file - it is not a permanent public URL.
• Nothing about the file content is logged or analysed.

Aspect ratio presets, and when each one matters

• 16:9 is the classic widescreen ratio. Use it for YouTube, Vimeo, embedded site players, and most desktop video. If your source is already 16:9, the preset is a no-op; use it as a sanity check before publishing.
• 9:16 is the vertical short-form ratio. TikTok, Instagram Reels, YouTube Shorts, Snapchat Spotlight and Facebook Reels all use 9:16. Cropping a 16:9 source to 9:16 keeps the full height and crops the sides; you almost always want to nudge X to keep the subject in frame.
• 1:1 is the square ratio. Instagram feed, Pinterest, and many display-ad placements. Square crops look balanced and avoid platform-side letterboxing.
• 4:3 is the classic SD ratio - useful for retro aesthetics, older social platforms, and some commercial digital signage. Custom rectangles cover everything else: 2.39:1 cinematic widescreen, 5:4 monitor, and arbitrary ad-server requirements.

How the crop works under the hood

FFmpeg's crop filter takes the form crop=W:H:X:Y where W, H, X and Y are integer pixel values. The filter slices a W-by-H pixel rectangle from each frame, anchored at the top-left corner (X, Y). Anything outside that rectangle is discarded; the inside is the new frame. We invoke FFmpeg with arguments equivalent to ffmpeg -i input -vf crop=W:H:X:Y -c:v libx264 -crf 20 -preset fast -c:a aac -b:a 192k output.mp4. The output is always MP4 with H.264 video and AAC audio; if you need WebM or MOV downstream, run the output through the video converter.

One subtle constraint: H.264 (and most other modern codecs) requires both width and height to be even numbers, because the chroma plane is subsampled by 2 in both dimensions. The tool rounds your inputs down to the nearest even number before sending, so you avoid the "width not divisible by 2" FFmpeg error that catches a lot of first-time users.

Use cases for the free video cropper

• Creators - reframe a 16:9 desktop recording to 9:16 for Reels or TikTok.
• Social media managers - produce a square 1:1 cut of a horizontal source for Instagram feed posts.
• Engineers and PMs - cut the chrome (browser toolbar, dock) off a screen recording before pasting it into a PR description.
• Photographers - reframe a B-roll clip for a portfolio site that uses a non-standard aspect.
• Researchers - crop out identifying information (faces, license plates, name tags) before sharing a clip.
• Educators - tighten the framing on a webcam recording so the speaker fills more of the frame.

Tips for clean cropping

• For TikTok and Reels, leave a bit of headroom above the subject. The platforms overlay UI on top of the video (caption, like button) and you want the focal point to stay visible after the overlay.
• Use the percent mode for batch-style crops where the same proportional region matters across files of different resolutions.
• If you need to crop then also speed up or slow down, run the crop first - retiming a smaller rectangle is faster than retiming the original.
• If the source has letterboxing (black bars), aim for the smallest rectangle that covers the live content; you do not need to be pixel-perfect, but trimming the bars saves bandwidth.
• Crop and resize are not the same thing. Crop drops pixels; resize stretches or shrinks them. For "fit this aspect without losing content" use both - crop to the aspect, then run the result through the video converter or compressor if you also need a smaller resolution.

Privacy and browser support

The tool works in any modern browser that can upload a file - recent Chrome, Edge, Firefox, Safari and mobile equivalents. There are no SharedArrayBuffer or cross-origin-isolation requirements. Files are uploaded over HTTPS to our EU-located processing server, cropped with FFmpeg, and made available via a signed, time-limited download URL. After 15 minutes both the input and the output are deleted from disk and the signed URL stops working. Nothing about your file content is logged or analysed.