Local Processing · FFmpeg WASM · No Upload
Video Cropper
Remove unwanted edges or reframe for vertical, square, or cinematic feeds. Drag a crop box over your browser-decodable video, pick an aspect ratio, preview a snapshot, and download the cropped MP4 — all in your browser.
video-cropper v2.0
1 Aspect ratio
2 Crop area (pixels)
Drag inside the box to move it, drag a corner to resize. Values are in source-video pixels and stay in sync with the box. Width and height are rounded to even numbers when processing.
Show crop log
Reframe a video in four steps
Upload, drag the crop box, process, download. Your video is cropped locally in the browser.
Upload video
Drop a file up to 10 MB. It is read from a local object URL, never uploaded.
Draw the crop
Drag the box, pull a corner, or type exact pixels. Presets snap to common ratios.
Check framing
Use the snapshot preview to verify the crop on the current frame before processing.
Crop & download
FFmpeg's crop filter cuts the frame; audio is preserved in the output MP4.
Precision, privacy, and predictability
What the cropper does with your video — and what it deliberately does not.
Zero upload
FFmpeg WASM runs in a worker inside your browser. Your uploaded video is processed locally in the browser and is not sent to a video-processing server.
Precise crop coordinates
The crop filter uses exact integer pixel offsets from the source frame — what you box is what you get, rounded to even dimensions.
Audio preserved
Cropping only changes the visible frame. The audio track is kept and re-encoded to AAC 128k for the output MP4.
Aspect ratio presets
One tap reframes your video for common display and feed formats.
16:9
Standard widescreen landscape format used for desktop and YouTube players.
9:16
Vertical full-height format commonly used for Shorts, Reels, and TikTok.
1:1
Square video format commonly used for social feed posts.
4:5
Portrait format commonly used for mobile vertical feed content.
4:3
Classic standard definition TV and older camcorder framing.
3:2
Photo standard framing typical in classic 35mm formats.
Free
No ratio lock — freely drag any rectangular area.
What it does, and what it does not
Clear boundaries so you know when to reach for another tool.
What it does
- Crop browser-decodable videos up to 10 MB.
- Visual drag-and-resize crop editor with corner handles.
- Seven aspect modes including vertical and square presets.
- Exact X/Y/W/H pixel inputs synced with the editor.
- Snapshot preview of the crop on the current frame.
- Keep audio; export MP4 with H.264 video, AAC audio, and the faststart flag.
What it does not
- Scale or upscale the cropped area (use Video Resizer after cropping).
- Rotate or flip the frame (use Video Rotator).
- Crop different regions over time (keyframed crops).
- Handle files above 10 MB — browser memory is the ceiling.
Common issues and fixes
Quick answers to common Video Cropper problems.
Engine won't load
The FFmpeg WASM engine needs WebAssembly and Web Workers, and its files must not be blocked. Exclude ffmpeg from JS minify/combine/delay in optimisation plugins, or self-host the engine files.
Crop box won't drag on mobile
The editor uses pointer events with touch-action disabled on the overlay. If your browser blocks it, use the X/Y/W/H inputs for exact placement instead.
Snapshot looks black
The snapshot uses the current playhead frame. Pause the video on a visible frame before clicking Preview crop.
Output dims differ by 1 px
H.264 requires even width and height, so the crop is rounded to the nearest even numbers and clamped inside the frame.
Frequently asked questions
Honest answers about the Video Cropper.
Is my video uploaded to a server?
No. The FFmpeg WASM engine runs entirely in your browser. Your video is read from a local object URL, cropped in memory, and never transmitted to AllInOneTools or any third party.
How does the crop editor work?
A draggable box overlays the video preview. Drag inside the box to move it, drag a corner handle to resize it, or type exact pixel values into the X, Y, W and H inputs — everything stays in sync.
Which aspect ratios are supported?
Free crop plus six presets: 16:9 (YouTube landscape), 9:16 (Shorts, Reels, TikTok), 1:1 (square feed), 4:5 (portrait feed), 4:3 (classic TV) and 3:2 (photo standard). Selecting a preset fits the largest matching rectangle centered in the frame.
Is the audio kept after cropping?
Yes. Cropping only changes the visible frame. The audio track is re-encoded to AAC 128k and kept in the output MP4.
Why are my crop dimensions rounded?
The tool rounds the crop width and height to even numbers for its H.264/yuv420p encoding path, then clamps the crop inside the source frame. As a result, the final crop can differ slightly from the values entered.
Why is there a 10 MB limit?
Re-encoding happens in browser memory. The 10 MB input limit helps reduce memory pressure, especially on devices with limited resources. For larger files, use a desktop tool like ffmpeg, HandBrake or Shutter Encoder.