Video Compressor
Compress a video to a target you type in MB, with presets at 16 for WhatsApp, 25 for email and 10 for Discord.
Runs entirely in your browser — your files and text never leave your device.
Drag & drop your file here, or
Target size finds the bitrate needed to land under the size you choose; quality keeps a consistent look with no hard size cap. Lowering the resolution is the biggest size saver.
Working on your device — keep this tab open until it finishes.
How to use
- Drop the clip on the Video field. Three cards appear with its duration, its pixel dimensions and its size on disk, which is the number you are trying to beat.
- Leave Compression on Target size when something else is imposing a limit, then type the megabytes in. The three buttons underneath fill it in for you: 16 for WhatsApp, 25 for email, 10 for Discord.
- Switch to Quality when no number is being forced on you. The three levels hand the encoder its own quality setting and the file lands wherever it lands.
- Set Max resolution if you can afford to lose pixels. It caps the shorter side of the frame and only ever shrinks, so 720p on a clip that is already 640×360 does nothing whatsoever.
- Press Compress and leave the tab open. The bar follows the encode, and Cancel stops it cleanly if you grabbed the wrong file.
- Read the four cards, play the result in the second player, then hit Download. It saves as compressed.mp4.
Where the megabytes go
A minute of 4K off a phone runs to a few hundred megabytes, and the WhatsApp preset on this page stops at 16. To compress a video down to a number like that, type it into Target size and let the arithmetic do the rest. Your megabytes become bits, 3% is held back as headroom, 128 kbps is set aside for the sound if the clip has any, and whatever bitrate remains after that is handed to the encoder for one pass. MB here means a million bytes, the way drives are sold, so 16 MB is 16,000,000 of them.
Quality mode works the other way round. Pick High, Medium or Low and the encoder aims for a consistent look with no size cap at all, which suits a clip that only needs to come down a bit. Max resolution sits alongside either mode and measures the shorter side of the frame, so 720p turns a 1920×1080 clip into 1280×720 and an upright 1080×1920 phone video into 720×1280. Losing pixels saves more than any bitrate you can choose, because there is less picture to describe in the first place. What comes out is an MP4 with H.264 video and AAC audio.
A 12-minute screen recording aimed at 25 MB
720 seconds of 1080p, target 25 MB. The budget is 194 Mbit after the 3% is held back, the audio takes 92 Mbit of that over the full 720 seconds, and the video is left with 141 kbps. At 1080p that is a smeared mess the moment anything moves on screen.
Set Max resolution to 480p and the clip comes out 854×480, which is a fifth of the pixels for the same 141 kbps, and the text in a screen recording stays readable. The four cards at the end report what actually happened: the original size, the compressed size, the percentage saved to one decimal place, and the dimensions you ended up with. If the encoder overshot and the file is still above your number, a warning underneath names the smallest size it managed.
Good to know
- Output is MP4 with H.264 and AAC, every single time. There is no way to keep a WebM as a WebM here, so run the result through the Video Converter when the container itself matters.
- It encodes once and never measures the result. The bitrate is arithmetic from your target and the clip's length, and encoders overshoot, so the file can land a little over the number you asked for. When that happens a warning tells you the size it actually reached.
- The video bitrate has a floor of 100 kbps. Ask for 1 MB on a ten-minute clip and the sums fall below that floor, the encoder gets the floor anyway, and what comes back is nearer 17 MB than 1.
- Max resolution is a ceiling on the short edge, and it never enlarges anything. Both sides are then rounded to an even number of pixels, which is what H.264 wants, so the result can sit a pixel off the exact aspect ratio.
- Audio is re-encoded to AAC at 128 kbps whatever it was before. Nobody will hear that on speech. On music with real top end you might.
Frequently asked questions
Is a megabyte here 1,000,000 bytes or 1,048,576?
It is 16,000,000 bytes, a megabyte counted as a million bytes. Anywhere that measures in mebibytes is working with 16,777,216 instead, so a file sized here comes in under their limit rather than over it.
Why did I get 15.2 MB when I asked for 16?
Three per cent of the budget is held back deliberately. Landing exactly on a limit is how you get rejected by a service that counts container overhead differently, so the real aim is 97% of the number you type.
I asked for 8 MB and the file came back at 17. What happened?
Your clip is long enough that the arithmetic fell under the 100 kbps floor the encoder is given, and the audio track costs another 128 kbps on top of that for every second. Trim the clip shorter first, drop Max resolution, or both.
Target size or Quality, which one should I use?
Target size when a limit exists and the file has to fit inside it. Quality when nothing is enforcing a number and you just want the thing lighter. Quality also sidesteps the trap of naming a size so small that no bitrate juggling can keep the picture watchable.
Does 720p do anything to a video that is already smaller than that?
Nothing at all. The cap only shrinks, and it looks at the shorter side, so a 640×360 clip passes straight through untouched and an upright 720×1280 phone video does the same.
How big a file can I put in?
There is no number written into the tool. The clip is decoded and re-encoded by your browser's own video engine, so the ceiling is the machine: a laptop takes a few hundred megabytes without complaint, a phone considerably less. A decode that fails gives you an error message rather than a silent stall.
What happens to the sound?
It comes across as AAC at 128 kbps. A clip that arrived with no audio track stays silent. To drop the sound on purpose, Mute Video does it without re-encoding the picture at all; to keep only the sound, Extract Audio pulls the track out.
Can I run the same file through twice to shrink it further?
You can, and it will get smaller, but the second pass is compressing an already-compressed picture and the artefacts compound. One pass at a lower resolution nearly always looks better than two passes down to the same size.
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