Compress a 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 a video
- 01A ▸Choose your videos, or drop them on the page. MP4, MOV, WebM, and MKV work.
- 02A ▸Pick a strength, or choose To a size and enter the largest size in MB.
- 03A ▸Check the size each video aims for, then select Compress.
- 04A ▸Download each video when the progress bar finishes.
Questions
Are my videos uploaded?
No. Your files are processed on your device. We never upload them.
How much smaller will my video get?
It depends on the video. Phones record at a high bitrate, so Balanced usually makes a phone video several times smaller with little visible change. A video that is already compressed (one downloaded from a site, say) shrinks less, and is never made larger than its original bitrate allows.
What do the strengths do?
Light keeps the size in pixels and a generous bitrate, so it looks the same. Balanced keeps up to 1080p at a lower bitrate. Strong makes larger videos 720p and saves the most space; it suits sharing in chats.
How does To a size work?
The tool works out the bitrate that fits the size over the video's length, keeping room for the sound and the file's own overhead. If the picture would look blocky at that bitrate, it makes the picture smaller instead. If the first try still comes out too large, it tries once more, lower.
How long does it take?
The picture is re-encoded frame by frame with your device's video encoder. On a computer the page shows an estimate under each video before you start. Phone timings are still to be measured; for long or 4K videos a computer is much faster.
Is there a size limit?
No fixed limit. The video is read and written in pieces, so it doesn't have to fit in memory. Over 100 MB the page asks you to confirm first, because a phone may run out of memory or storage.