Crop Video
Processed locally in your browser — nothing is uploaded.
Quick answer
To crop a video, you cut the frame down to a new rectangle — trimming the sides or top and bottom to reach an aspect ratio like 1:1, 9:16, 16:9 or 4:5. This tool does it in your browser with ffmpeg.wasm, so nothing is uploaded, and gives you the exact shape Instagram, TikTok or YouTube expects. A one-time ~32 MB engine loads on first use; short clips work best.
How to crop video
Load your video
Drop your clip in. On first use the ~32 MB engine downloads and caches, then starts instantly afterwards.
Pick an aspect ratio
Choose 1:1 square, 9:16 vertical, 16:9 wide or 4:5 portrait, and position the crop box over the part of the frame you want to keep.
Crop and download
Export the cropped video. Because cropping re-encodes the frame, expect a single-threaded wait on longer clips.
Is cropping the same as resizing?
No, and the difference matters. Cropping cuts pixels away — it changes the shape of the frame and throws out whatever falls outside the box, so a wide clip becomes a square by losing its sides. Resizing keeps the whole frame and scales it to fewer pixels, changing the size but not the shape. Reach for cropping when the *aspect ratio* is wrong for where the video is going; reach for resize when the frame is the right shape but too large.
Which aspect ratio does each platform want?
Every social platform frames video differently, and posting the wrong ratio means ugly bars or an automatic crop that chops off heads. Crop deliberately so you control what stays in frame.
| Ratio | Shape | Where it fits |
|---|---|---|
| 9:16 | Tall vertical | TikTok, Reels, Shorts, Stories |
| 1:1 | Square | Instagram feed, Facebook feed |
| 4:5 | Portrait | Instagram feed (takes more height) |
| 16:9 | Wide | YouTube, landscape players, TVs |
How do you avoid cutting off the subject?
The single biggest risk when cropping wide footage to vertical is losing the subject off the side. A few habits help:
- Position the crop box on the subject before you export, not on the centre by default.
- When cropping 16:9 down to 9:16 you keep only the middle third — make sure the action lives there.
- Leave a little headroom so faces are not pinned to the top edge.
- If the subject moves across the frame, a fixed crop cannot follow them; trim to a steadier section first with trim video.
What are the browser limits?
Cropping re-encodes every frame, so it runs at the same single-threaded WebAssembly speed as compression — fine for a short social clip, slow for anything long, and memory-bound on very large files. That is the honest trade for a private, install-free tool: keep the input to the length you would actually post, and the workbench will warn you and let you cancel if a file is too big.
Is my video uploaded to crop it?
No. The crop runs in your browser through ffmpeg.wasm — your file is processed in memory and handed back as a download, never uploaded. Check DevTools → Network to confirm no request is made, and note it keeps working with the internet disconnected once loaded. Your footage stays private.
Related video and subtitle tools
If the frame is upright but sideways, rotate the video first. To shrink the cropped clip for upload, compress it or resize it. And once it is framed for vertical, add subtitles — captions lift watch time on muted mobile feeds — or prepare them first with the subtitle converter.
Your files never leave your device
Processed locally in your browser — nothing is uploaded. You can verify it yourself: open your browser’s developer tools, watch the Network tab, and use the tool — no upload request is ever made.
Frequently asked questions
How do I crop a video to a square for Instagram?
Choose the 1:1 ratio, position the crop box over your subject, and export. The tool cuts the frame to a perfect square without stretching, ready for the Instagram feed.
How do I turn a landscape video into a vertical one?
Crop to 9:16. That keeps a tall slice — roughly the centre third of a 16:9 frame — so make sure your subject sits in the middle before exporting, or it will be cut off.
Does cropping stretch or distort the video?
No. Cropping removes the area outside the box and keeps the rest at its original scale. Nothing is stretched or squashed, so the footage that remains stays sharp.
Will I lose quality by cropping?
The kept pixels are unchanged, though cropping re-encodes the frame, which adds the usual small encode loss. Use a low CRF if you plan to compress afterwards to keep it minimal.
What aspect ratio is best for TikTok and Reels?
9:16 vertical fills the screen on TikTok, Instagram Reels and YouTube Shorts. Anything wider shows bars or gets auto-cropped by the app, often badly.
Can the crop follow a moving subject?
No. The crop box is fixed for the whole clip, so it cannot track motion. If your subject moves across the frame, trim to a steadier section or reframe with a wider crop.
Is cropping done on my device?
Yes, entirely in your browser via ffmpeg.wasm. No upload happens — you can confirm there is no network request in your developer tools.