My Tool Studio
Video

Video Compressor

A two minute phone clip can easily weigh a few hundred megabytes, which is far past what email or chat will accept. This video compressor online shrinks it without leaving your browser: FFmpeg compiled to WebAssembly does the encoding on your own CPU, so the file is never uploaded. Use it as an mp4 compressor with H.264 for maximum compatibility, or pick WebM VP9 for smaller output at the same quality. You can compress video free with the CRF quality slider, or flip to Target size mode, type the megabytes you need, and let it work out the bitrate. Trim, crop, drop to 720p, lower the frame rate, or mute the audio to reduce video file size online even further.

Always freeNo sign upRuns in your browser

How to use

01

Load your clip

Drag in an MP4, MOV, WebM, MKV, or AVI file. The tool reads its size, duration, and resolution locally and shows a playable preview; nothing is uploaded.

02

Choose format and compression mode

Pick MP4 or WebM, then either the Quality (CRF) slider with High quality, Balanced, and Small file presets, or Target size in MB. Optionally set Resolution, Crop aspect ratio, Frame rate, Trim, or mute.

03

Compress and download

Hit Compress video. The first run fetches the 30 MB engine, then progress runs to 100 percent, shows the before and after sizes, and offers the download.

Why Video Compressor

Common questions

What CRF value should I use to compress a video?
For MP4 the slider runs 18 to 34 with 23 as the balanced default; WebM runs 24 to 44 with a default of 33. Lower means better quality and a bigger file. If you don't want to think about it, the High quality, Balanced, and Small file presets pick sensible points on that range.
How does Target size mode hit an exact video file size?
It takes your target in MB, divides by the clip's duration after trimming, reserves 128 kbps for audio, and sets the video bitrate to land just under the number you asked for. It's the mode to use when a form or platform enforces a hard upload cap.
Should I export compressed video as MP4 or WebM?
MP4 with H.264 plays essentially everywhere: phones, editors, PowerPoint, every social platform. WebM with VP9 usually comes out noticeably smaller at matching quality but has patchier support in older software. Default to MP4 for sharing; pick WebM for web embedding.
Why does the video compressor fetch a 30 MB engine first?
The encoder is FFmpeg compiled to WebAssembly, and that binary downloads on your first compression, then stays cached. It's the tradeoff for full local processing: one download up front, and afterwards your footage never has to travel to a server.
Can I compress video free without a watermark or account?
Yes. There's no sign-up, no upload quota, and no watermark stamped on the output. The practical limits are your browser's memory and your CPU speed rather than a paywall.
Is there a limit on how large a video I can compress in the browser?
There's no enforced cap, but files over roughly 500 MB risk hitting browser memory limits, and the tool warns you at that point. If a big file fails, trim it into sections, lower the Resolution to 720p or 480p, or compress the pieces separately.
Does muting the audio reduce video file size online by much?
The audio track costs 128 kbps here, about 1 MB per minute. On a large high-bitrate video that's pocket change, but when you're squeezing a clip under a 10 MB chat limit, muting hands that entire budget back to the picture.
Where does the video compression actually run?
Entirely on your device. FFmpeg.wasm executes in the browser sandbox, reads the file from local memory, and writes the compressed result back as a download. It even works offline once the engine is cached, which no upload-based mp4 compressor can claim.