Compress Video Online Free

Frequently asked questions

How do I compress a video online?

Upload your MP4. Choose Light, Medium, or Strong. Click "Compress video". FFmpeg.wasm re-encodes in your browser. When done you see original and new size; download the result. Processing can take several minutes for long videos.

Are my videos sent to a server?

No. Compression runs entirely in your browser using FFmpeg.wasm. Your video never leaves your device.

What do the compression levels mean?

Light: CRF 28, good quality, ~40% smaller. Medium: CRF 33, balanced, ~60% smaller. Strong: CRF 38, smaller file, lower quality, ~75% smaller.

Why does compression take so long?

Re-encoding video is CPU-intensive. FFmpeg.wasm runs in the browser, so speed depends on your device. Long or high-resolution videos can take several minutes.

What format is the output?

The output is MP4 (H.264 video, AAC audio), suitable for web and sharing.

Does it work on mobile?

Yes, but compression is CPU-intensive. On phones it may take longer; short clips work best.

Can I compress WebM or other formats?

This tool accepts MP4 input and produces MP4 output. For other formats use a converter first or a desktop app.

Is there a file size limit?

There is no fixed limit. Very large videos may use a lot of memory and take a long time. Limits depend on your device.

Why use browser compression?

No upload to a server—your video stays on your device. Useful for quick size reduction when you cannot install software.

Does it work in all browsers?

FFmpeg.wasm requires a modern browser with WebAssembly. Chrome, Firefox, Safari, and Edge (recent versions) work.