Compress Video Online for Free
Make a video file smaller without leaving your browser. Works with MP4, MOV, MKV, WebM, AVI and more. No upload, no signup, no watermark.
Click or drag & drop to upload your file
Why compress video with Whisper Web?
Stays on your device
Compression runs in your browser. Your video is not uploaded to a server, so there is nothing to wait for and nothing to delete afterwards.
Free, no signup
No account, no watermark and no daily limit. Open the page, drop a file and download the result.
See the size first
Pick a level and the page shows an estimated size for your file before you start, so you can choose the smallest file that still looks right.
Fast on modern browsers
Uses your device's video encoder when the browser offers one, and a built-in engine when it does not.
How to compress a video
- 01
Choose your video
Drop a file onto the box or click Select a file. Nothing leaves your device.
- 02
Pick a compression level
Smallest file, Best balance or Best quality. Each one shows the size you can expect for your file.
- 03
Compress and download
Click Compress, wait for the progress bar to finish, and download your smaller MP4 video.
Free online video compressor
What a video compressor does
A video compressor lowers the amount of data each second of video uses, so the file takes less space and moves faster. This one runs entirely in your browser: choose a file, pick how small it should get, and download the result.
Why shrink a video file?
Large videos are slow to upload, easy to push past attachment limits, and heavy on phone and cloud storage. A few minutes from a recent phone can take hundreds of megabytes. Compressing lowers the bitrate, which is how much data each second of video uses, so the file gets smaller while the picture stays watchable.
When a smaller video helps
Sending a clip by email or chat, uploading to a form with a size cap, freeing space on your phone, sharing a screen recording, or archiving old footage. If the place you are sending it to has a size limit, start with Smallest file and check the size shown in the result.
How the compression works
The tool re-encodes the video as H.264 with AAC audio, the combination that plays almost everywhere. It reads the length and size of your file and picks a bitrate that lands near the level you chose. For Smallest file and Best balance it also scales frames taller than 720p or 1080p down, because fewer pixels need fewer bits. When your browser offers a hardware video encoder the tool uses it, which is usually several times faster than playback speed for HD video on a recent computer. Otherwise it falls back to a built-in WebAssembly engine that is slower but follows the same settings.
Formats it handles
MP4, MOV, MKV, WebM, AVI, WMV, FLV, M4V, MPEG, 3GP and most other common video files. The result is an MP4 file with H.264 video and AAC audio.
What each level does
Smallest file aims to remove about 70% of the size and limits the picture to 720p. Best balance aims at about 50% and limits it to 1080p. Best quality aims at about 30% and keeps the original resolution. These are targets, and the size the page shows for each level is estimated from your file. Videos that are already compressed shrink less than clean, high-bitrate recordings.
Frequently asked questions
How do I reduce a video's file size?
Drop your file onto the box, choose a compression level, click Compress and download the result. The tool lowers the video's bitrate and, for the smaller levels, its resolution. Everything happens in your browser.
How much smaller can a video get?
The three levels aim for about 70%, 50% and 30% smaller. Recordings from phones and cameras usually reach those targets. A video that was already compressed, such as one downloaded from a streaming site, has less to give and may shrink by only a few percent. The page tells you when that happens.
Does compressing a video reduce its quality?
Yes, a little. Compression works by throwing away detail the eye is unlikely to miss, so the smaller the file, the more detail goes. Best quality keeps the original resolution and removes the least. Smallest file is meant for sharing, not archiving.
Which video formats can I compress?
You can compress MP4, MOV, MKV, WebM, AVI, WMV, FLV, M4V, MPEG and 3GP files, along with most other common video files. The result is an MP4 file with H.264 video and AAC audio, which plays on nearly every phone, computer, TV and video editor. If you want to keep a MOV or MP4 container, use the MOV or MP4 compressor instead.
How do I compress a video for Discord?
Discord limits the size of uploads for free accounts, and the limit changes from time to time, so check the current number first. Then choose Smallest file, look at the size in the result, and if it is still too big, trim the clip or compress it a second time from the original.
Is there a file size limit?
Files up to 2 GB are accepted. Files over 500 MB can take a long time and need a lot of memory, so close other tabs first. There is no limit on how many files you compress.
Can I compress a video without losing quality?
Not completely. Any method that makes a video meaningfully smaller removes some information. Best quality is the closest this tool gets: it keeps the resolution and aims at a 30% smaller file.
Can I compress a video on my phone?
It runs in the browser, so it can work on a phone, but we have mainly tested desktop browsers. Phones have less memory and slower encoders, so long or large videos are more reliable on a computer.
Are my videos uploaded?
No. The file is read and compressed inside your browser, and the result is created on your device. Only the page and the compression code are downloaded.