Shrink any video to a target size, right in this tab
Tell the tool what the file needs to weigh — 16 MB for WhatsApp, 10 MB for an email — and it re-encodes your video with the exact bitrate that hits that size. Decoding and encoding both happen inside your browser; the video never leaves your device.
- 100% local · nothing uploaded
- Fit-to-size bitrate math
- Resolution scaling
- No sign-up, no watermark
Compression settings
Your compressed video is ready
Compressed entirely in your browser. Open the Network panel in your browser's developer tools while using this tool — no file ever leaves your device.
Bitrate Math, Not Magic
Every video file is essentially bitrate × duration. If you know how long the video is and how big the file is allowed to be, the bitrate writes itself — that is the entire idea behind this tool.
Pick the target size
Choose a limit — a chat app cap, an email cap, or a custom number. The tool reads your video's duration and computes the exact bitrate that lands on that size.
Calibrate & re-encode locally
The video is decoded frame by frame and re-encoded by your browser's engine at the computed bitrate. A short sample pass first measures how much bitrate your encoder actually delivers — browsers routinely ignore the number you ask for — and the request is corrected before the full run, the same two-pass logic FFmpeg uses.
Preview and download
Watch the result right on the page before committing. If it's too soft, raise the target size or drop the resolution — smaller frames need fewer bits to look clean.
The Honest Physics of Compression
Compression is a trade between size and fidelity, and every tool on earth plays by the same rules. Here's what that means for your file.
Built for
- Chat & email caps — WhatsApp's 16 MB, Gmail's 25 MB, custom limits
- Phone recordings — minutes of 1080p footage with room to shed
- Screen recordings & demos — content that compresses gracefully
- Web sources — MP4 and WebM inputs re-encode cleanly
Trade-offs
- Quality loss is real — a 200 MB file crushed to 10 MB will visibly soften
- Processing runs at playback speed — a 5-minute video takes about 5 minutes
- Output format follows your browser — MP4 (H.264) where supported, WebM (VP9) elsewhere
- No trimming, no editing — cut the video first if you only need part of it
Three Ways to Compress a Video
Browser, desktop, or cloud — the differences that actually matter are privacy, output format control, and what happens when your video is three gigabytes.
| This tool | Desktop (HandBrake, FFmpeg) | Online compressors | |
|---|---|---|---|
| Your file leaves the device | Never | Never | Yes, uploaded to servers |
| Cost | Free | Free, open source | Free tiers with limits |
| Output format control | Browser-dependent | Full codec control | Usually full |
| Speed for long videos | Playback speed | Faster than realtime | Server farms |
| File size ceiling | Device memory | Practically none | Plan limits |
| Install required | No | Yes | No |
Other Well-Known Ways to Compress a Video
The right tool depends on how much control you need and where you're willing to let your video travel. These are the established options.
HandBrake
The veteran open-source transcoder. Full control over codecs, quality targets and frame rates, faster than realtime on any modern laptop — at the cost of installing software and learning its presets.
handbrake.fr ↗FFmpeg
The engine underneath half the internet's video. One command line re-encodes anything to anything, with two-pass bitrate targeting identical in spirit to this tool. Unmatched power, real learning curve.
ffmpeg.org ↗CloudConvert & FreeConvert
Polished web-based converters with real server-side encoding — fast, format-flexible, and free tiers with daily caps. Your video is uploaded to their infrastructure to be processed.
cloudconvert.com ↗Clipchamp
Microsoft's bundled video editor (built into Windows 11) compresses as a side effect of exporting. Good choice when you also want trimming or captions, though it wants an account and sends your project to Microsoft's cloud.
clipchamp.com ↗Frequently Asked Questions
Short, direct answers — the kind you can quote.
How much can you compress a video before it looks bad?
As a rule of thumb, 1080p footage stays presentable down to about 1 bit per pixel per frame region — roughly 4–5 Mbps for moving content. Below that, flat areas get blocky and fine detail smears. A six-second clip fits 10 MB comfortably at high quality; a ten-minute clip squeezed to 10 MB (about 130 kbps) will look like a 2005 webcam. Shorter target, smaller resolution, or trim first.
What is video bitrate, in plain words?
Bitrate is how many bits of data the file spends per second of video. A 12 Mbps video uses twelve million bits every second; a 60-second clip at that rate weighs about 90 MB. Bitrate times duration equals file size, which is why the tool asks for your target size and duration does the rest. Codec efficiency (H.264, VP9, AV1) determines how good those bits look.
Why does the output sometimes come out as WebM instead of MP4?
The tool re-encodes using your browser's built-in recording engine, and every browser supports a slightly different set of output formats. On current Chrome and Edge it produces MP4 (H.264); on Firefox and some others it falls back to WebM (VP9). WebM plays everywhere modern — browsers, Android, VLC — but some older software expects MP4. The page shows which format your browser will produce before you start.
Why does compression take as long as the video itself?
Because the tool plays your video through the browser's media engine and re-encodes it in real time as it plays. Server-based compressors throw multiple CPU cores at the file in parallel, which is faster — but that's only possible because the file lives on their machines. The trade is speed for privacy.
Is the compressed file smaller for sure?
The tool runs a short calibration pass before encoding, because browsers' built-in encoders routinely deliver only a fraction of the bitrate you request. The measured ratio corrects the main pass, so output lands close to your target — typically within 10–15% for normal-length videos. Two honest caveats remain: very short clips with generous targets can bump into the encoder's internal rate ceiling (the file comes out smaller than the target, never larger), and an already-efficient file can grow slightly when re-encoded. Neither harms the video; the first just means you got the quality for free.
Does it compress audio too?
Audio is re-encoded alongside video at a modest stereo bitrate (about 96–128 kbps). For size-critical jobs you can drop the audio track entirely — a music video becomes useless without sound, but a screen recording or security camera clip loses nothing.
Is there a file size or length limit?
No artificial limit — the practical ceiling is your device's memory, since the video has to load and decode locally. Clips of a few hundred megabytes handle fine on a typical laptop; a multi-gigabyte movie is a job for HandBrake or FFmpeg, and the comparison table above says as much.
Is my video uploaded anywhere?
No. The tool is a single page that decodes and re-encodes video inside your browser tab. There is no server, no API call and no analytics on your file. Verify it yourself: open your browser's developer tools, watch the Network tab and compress a video — nothing is sent.
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