About Compress Video
Compress Video — free, private, browser-based video tool
Make a video file smaller for email, WhatsApp or upload limits. Choose a quality level and download an MP4.
Why use Compress Video
- ·Files stay on your device — nothing is uploaded
- ·No signup needed
- ·Works in any modern browser, on any OS
- ·Free daily use; Pro removes limits and watermarks
How to use it
- 1Drop the video (MP4, MOV, WebM…).
- 2Choose Visually Lossless, High Quality, Web Standard (default) or Small File.
- 3Press Compress & Download and wait for the progress bar; you get an H.264 MP4.
Quality levels
Visually Lossless (CRF 18), High Quality (CRF 22), Web Standard (CRF 26, the default) and Small File (CRF 30). The video is re-encoded to H.264 with AAC audio at 128 kbps and saved as an MP4 that starts playing before it has fully downloaded.
Engine and limits
Encoding runs with ffmpeg compiled to WebAssembly, on your device. Free use covers videos up to 5 minutes; long or 4K videos take a while in the browser.
How it works
Hybrid renderer: WebGL2 for color grading and effects, WebCodecs for decode/encode, ffmpeg.wasm for muxing and exotic codecs. Multi-threaded via SharedArrayBuffer where COOP/COEP is available. The processing code runs inside the page, so your file is not uploaded to a server — you can confirm this in your browser's DevTools → Network tab.