Compress an MP4 video
Your files are processed on your device. We never upload them.
Video is read and written with Mediabunny, under the Mozilla Public License. Browsers without their own AAC encoder use FFmpeg's, under the GNU LGPL.
How to compress an MP4 video
- 01A ▸Choose your MP4 videos, or drop them on the page.
- 02A ▸Pick a strength, or choose To a size and enter the largest size in MB.
- 03A ▸Select Compress, then download each MP4.
Questions
Are my videos uploaded?
No. Your files are processed on your device. We never upload them.
Why are phone MP4s so large?
Phones record at a high, steady bitrate so fast movement never looks blocky: about 16 to 20 Mbps for 1080p and 40 to 60 Mbps for 4K, roughly 120 MB and 400 MB a minute. Most clips need far less to look the same.
What do I get back?
An MP4 with H.264 video and AAC sound, the pairing every phone, browser, TV, and editor plays. HEVC (H.265) iPhone videos come back as H.264, which plays in more places.
How much smaller does it get?
Our one-minute 1080p MP4 sample (61.1 MB, H.264 at 8 Mbps) came out at 43.1 MB with Light, 29.0 MB with Balanced, and 8.1 MB at 720p with Strong, each in about 5 seconds in Chrome on a laptop. It is a synthetic test pattern; phone footage, recorded at a higher bitrate, usually shrinks more. Phone timings are still to be measured.
Will compressing again make it smaller still?
Each compression loses a little detail, and a well-compressed MP4 has little left to give. Compress the original once, at the strength you need.
Is the result ready for streaming or the web?
Yes. The MP4's index is written at the start of the file, so it starts playing before it has fully downloaded.