Video Compressor
Shrink a video into a smaller MP4 without uploading it anywhere. Choose a quality level and resolution, and H.264 re-encoding happens entirely in your browser — no watermark, no sign-up to try.
Heads up: compression runs entirely in your browser, so it is best for short clips (roughly under ~1–2 minutes / ~100 MB). Large videos are slow and can run out of memory.
Your compressed MP4 will appear here once the tool finishes re-encoding.
Free preview — sign in (Google or email) to download. We use sign-in only to keep the tool free of abuse.
How in-browser video compression works
This tool re-encodes your video with the H.264 codec at a quality you choose, and it does all of that work directly in your browser using WebAssembly — a full copy of FFmpeg compiled to run on the web. Because the encoding happens on your own device, the video is never uploaded to a server. Nothing leaves your computer, nothing is stored on our side, and no account is needed to try it. You drop in a file, pick how aggressive the compression should be, and download a fresh MP4.
The quality dial is CRF (Constant Rate Factor): a lower number keeps more detail but produces a bigger file, while a higher number squeezes harder and saves more space. High quality (CRF 23) stays close to the original, Balanced (CRF 28) is a sensible middle ground for sharing, and Small file (CRF 32) trims the most. Dropping the resolution to 720p or 480p saves even more. Be honest with yourself about the trade-off: doing this in a browser tab is slower than a dedicated server and works best on short clips — roughly under a minute or two. Long, high-resolution videos can be slow or run out of memory, so trim first when you can.
How to use
- 1
Add your video.
Drag a file onto the drop zone or click to browse. MP4, MOV and WebM all work, and the file stays on your device.
- 2
Choose quality.
Pick High quality, Balanced or Small file. This sets the CRF — lower keeps detail, higher saves space.
- 3
Pick a resolution.
Keep the original or scale down to 720p or 480p for an even smaller file. The aspect ratio is preserved.
- 4
Compress.
Hit Compress video. The engine downloads once (~30 MB, then cached) and the progress bar tracks the real encode.
- 5
Sign in and download.
Check the size saved and the preview, then grab your compressed MP4. The download is free.
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Shrink JPG, PNG and WebP in your browser with the same no-upload, private approach.
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Swap between PNG, JPG and WebP locally when you need a different container.
Remove image backgrounds
Cut the background from any photo on-device and export a clean transparent PNG.