Compress a video online — in your browser, no upload
Pick a target size and Cutmoor calculates a video bitrate that fits. The file is decoded and re-encoded on your device, not on a server. Use it when an app rejects a video for being too large, or when a 4K clip is 400 MB and you only need a clean 1080p share.
From file to download, with no upload bar
- 01Choose the video
Drop an MP4, MOV, WebM, or MKV file. Metadata is read locally to calculate the right bitrate.
- 02Pick a target
Select a preset such as 25 MB for Instagram or 10 MB for Discord, or choose a quality-first CRF encode.
- 03Compress and download
The browser encoder produces a new MP4. Nothing is uploaded while it runs.
Compress video: common questions
Will compression make my video blurry?
Some quality loss is unavoidable when the file gets smaller. Cutmoor keeps the original resolution unless you lower it, and it reserves 128 kbps for audio so dialogue stays clear. For a mild reduction, use the Balanced preset instead of an aggressive target size.
What is the best target size for WhatsApp?
WhatsApp compresses videos again when you send them as media, so aim below the app limit and keep the resolution at 720p or 1080p. If you need the exact file, send it as a document instead of a video.
Does Cutmoor upload my video?
No. The encoder is WebAssembly running inside the page. The file is read from your disk, processed in memory, and saved back to your device. You can disconnect from the internet after the page loads and the tool still works.
How large a file can it handle?
Browser memory is the limit, not an upload quota. Files up to roughly 500 MB work on a desktop with 8 GB of RAM. Phones and older laptops should stay under 200 MB. Very large files can run out of memory in the tab.