Compress a video

How it works

1. Drop an MP4, M4V or MOV. One video at a time: the whole file is held in your browser while it works.
2. Either aim for a size — 25 MB is the Gmail attachment limit — or leave that on No target and pick a quality instead. Choosing a target hides the quality setting, because the target decides it.
3. Lower the resolution if the video does not need to stay sharp at full size. Going from 1080p to 720p roughly halves the file before quality is even considered, and it is the single biggest saving available. The number caps the longest side, so an upright phone clip gets it as its height — and a 1080x1920 clip is left alone by Up to 1080p.
4. Press Compress video. Every frame is decoded, scaled and re-encoded on your device, so expect it to take a fraction of the clip's own length on a desktop and longer on a phone.
5. Download the MP4. The file keeps its name with -compressed added.

Frequently asked questions

Is my video uploaded?

No, and for video that is the whole point. A video is the largest file most people ever send: uploading one is slow, it burns mobile data, and holiday or family footage is exactly what you would not hand to a website. Here the file is read, re-encoded and written on your device, by the browser's own encoder.

Why is there nothing to download first?

Because the codec is already in your browser. The usual way to do this on the web is to ship a 32 MB build of FFmpeg as WebAssembly, which is both a large download and much slower, since it encodes in software. This uses WebCodecs, the browser's own interface to the hardware encoder your device records video with.

How small will it get?

It depends on what the video is and how it was recorded. A phone clip recorded at a high bitrate often loses half to three quarters of its size at Balanced quality with no visible change; a clip that is already compressed for the web may barely shrink, and if the result comes out no smaller than the original — within a couple of per cent — you get the original back rather than a pointless re-encode. Dropping the resolution saves more than any quality setting.

Will it hit the size I asked for?

Close to it. The bitrate is worked out from the length of the clip and the size you asked for, with a few per cent kept back, so the result usually lands just under. It is one pass, not a search: a clip of fast-moving detail can come out a little over, so check the size before you send it if the limit is hard. One thing to know about mail in particular: attachments are encoded for transport, which adds about a third to what you send, so a file just under 25 MB can still bounce. If the limit is hard, aim for 10 MB.

Which files does it take?

MP4, M4V and MOV, which covers phone recordings, screen recordings and most cameras. WebM and AVI are not read: the part that takes the file apart understands MP4 only. Whether the video inside can be decoded is down to your browser — H.264 works everywhere, and HEVC (the format newer iPhones record in) works in Safari and in Chrome on hardware that supports it.

What happens to the sound?

An AAC track, which is what a phone or a camera records, is copied across untouched rather than re-encoded, so it loses nothing. Some MOV files from camcorders and DSLRs carry uncompressed PCM instead, and some files carry AC-3; neither can be copied that way; rather than drop it silently the tool says so and asks you to choose Remove the sound. Removing it is worth doing anyway for a screen recording nobody needs to hear: sound costs upwards of a megabyte a minute, more when it was recorded at a high rate.

Will a video I shot upright come out sideways?

No. A phone records landscape frames whichever way you hold it and writes down which way up the picture should be; that instruction is carried across to the new file, so it plays the way you shot it.

Which browsers can do this?

Chrome and Edge, Safari 16.4 and newer, and Firefox 130 and newer. An older browser is told plainly when you press the button, rather than grinding through the file and failing at the end.

What are the free limits?

One video per run at 150 MB and 10 runs a day on the free plan, which is about a minute of 1080p phone video. Pro removes both, and the real ceiling after that is your device's memory. Nothing is watermarked and there is no account to make: the free plan limits how much you can run, not what you get back.