Compress Video
Compress Video shrinks a video to fit Discord, WhatsApp or email by re-encoding it to H.264 MP4 with WebCodecs in your browser, so the video is never uploaded.
At a glance
- Accepts
- MP4, MOV, WebM and MKV videos your browser can decode (HEVC needs Safari or a recent Chrome/Edge)
- Outputs
- An H.264 MP4 under a chosen size (16, 18, 20 MB or custom) or at a chosen quality; HDR is converted to SDR
- Where it runs
- Entirely in your browser, on your device
- What leaves your device
- Nothing - the file never leaves your device
- Limits
- Needs WebCodecs (not in Firefox for Android); up to 30 min and 4 GB on phones, 4 hours on computers; long videos can't fit small sizes and it says so
- Account
- Not required - there is no sign-up
- Price
- Free, with no watermark and no usage cap
- Made by
- Visrut
- Last updated
- 13 October 2026
Pick where the video is going - Discord, WhatsApp or email - and the video comes back as an MP4 that fits under that limit, at the highest resolution the size allows. It is re-encoded in your browser with WebCodecs, which uses your device's hardware video encoder where there is one, so a minute of 1080p usually takes well under a minute on a recent laptop or phone. Nothing is uploaded.
How to use it
- Drop in a video, or click to choose one.
- Choose a size: Discord (20 MB), WhatsApp (64 MB), email (18 MB), a custom size, or a quality level if size doesn't matter.
- Press Compress. The plan shown before you start says what resolution and bitrate it will use and roughly how big the file will be.
Why the limits are what they are
- Discord: free accounts can upload 20 MB per file since August 2026 (it was 10 MB before that). Nitro raises it.
- WhatsApp: its help centre now gives 64 MB for videos on slower connections and 100 MB on faster ones (an older article still says 16 MB), so the preset is 64 MB, which works on any connection. Sending as a document allows up to 2 GB, but then it doesn't play inline.
- Email: Gmail's 25 MB limit counts the attachment after email encoding, which makes it about a third bigger, and Outlook stops at 20 MB. 18 MB gets through both.
Honest limits
- Long videos and small targets don't mix: 20 MB holds a little under two minutes of 720p with sound. Past what fits at a watchable quality, it says so instead of producing mush.
- Hardware encoders are fast but less efficient than a slow desktop encoder like x264, so a desktop app can squeeze slightly more quality into the same size.
- On phones it handles videos up to 30 minutes and 4 GB; on computers, up to 4 hours. The tab has to stay open, but it keeps working in the background.
Frequently asked questions
Is my video uploaded anywhere?
No. The video is decoded and re-encoded inside your browser tab with WebCodecs, the browser's own video encoder (usually your device's hardware encoder). Nothing is sent to a server, which also means there is no upload to wait for.
How does it hit an exact size like 16 MB?
It divides the size by the video's length to get a bitrate, keeps the audio as it is when that fits, and picks the largest resolution that still gets enough bits per pixel to look decent. Hardware encoders don't land exactly on a bitrate, so the result is measured; if it came out over the limit, it is encoded once more, lower.
Why is my iPhone video grey or washed out after other compressors?
iPhones record HDR (HLG, BT.2020). A converter that ignores that produces flat, grey colours. This one reads the HDR tags and converts the picture to standard dynamic range on the GPU, so the output looks like the original on any screen.
What if the video is too long for the size?
Below a certain bitrate every encoder turns video into mush, so instead of producing that, it tells you how many seconds would fit. Trim the video first, or pick a bigger target.
Which browsers work?
Chrome, Edge and Safari 16.4+ on computers and phones, and Firefox 130+ on computers. Firefox for Android does not support WebCodecs yet. HEVC (H.265) files, the iPhone default, need a browser with an HEVC decoder: Safari, or Chrome and Edge on most recent Macs and Windows PCs.
What do I get?
An MP4 with H.264 video and AAC audio (Opus in Firefox, which has no AAC encoder), the most widely playable combination: Discord, WhatsApp, email clients, PowerPoint and every phone play it.