Video Compressor

Compress MP4, MOV, AVI, MKV or WebM videos with H.264 encoding. 100% private, runs in your browser.

Drop your video here

or click to browse from your device

MP4, MOV, AVI, MKV, WebM supported

How to Compress a Video

1

Upload Video

Drop or select your MP4, MOV, AVI, MKV or WebM file. Your video never leaves your device.

2

Choose Compression

Pick a quality level or set a custom CRF value to control the trade-off between file size and quality.

3

Set Resolution

Optionally downscale to 1080p, 720p, 480p, or 360p to further reduce the file size.

4

Download

Click Compress and save the smaller video file to your device once processing is complete.

Frequently Asked Questions

CRF stands for Constant Rate Factor — it controls quality in H.264 encoding. Lower values (18–23) produce higher quality with larger files. Higher values (28–51) produce smaller files with lower quality. CRF 23 is the default for a good balance, and 28 is commonly used for web sharing where file size matters more.

For sharing videos via email or messaging apps, Medium (CRF 28) is usually the best choice. If you need to preserve quality for archiving or professional use, choose Low (CRF 23). High (CRF 33) is suitable when you need the smallest possible file and can tolerate some quality loss, such as for previews or drafts.

Only if you choose a resolution option other than "Original". By default the resolution stays the same and only the bitrate is reduced using CRF encoding. Selecting 720p or lower will scale the video down proportionally, which is one of the most effective ways to dramatically reduce file size.

It depends on the original encoding. Videos recorded on phones or cameras are often only lightly compressed and can be reduced by 50–80% with minimal visible quality loss. Videos that are already heavily compressed (e.g. downloaded from streaming services) will see smaller gains. Combining CRF compression with a resolution reduction typically yields the biggest savings.

No. This tool uses FFmpeg compiled to WebAssembly (FFmpeg.wasm) which runs entirely inside your browser. Your video data is processed locally on your device and is never transmitted to any server. Your content stays completely private.