Video compressor
FileReshape's video compressor re-encodes a video as an H.264 MP4 with the compression and resolution you choose, using FFmpeg inside your browser. The video is not uploaded and gets no watermark. A phone video often shrinks to a third or less. Encoding runs on your own device, so long or 4K videos take several minutes.
Did a file not convert correctly? E-mail [email protected], ideally with a small sample file, and it will be fixed.
Key facts
- Works with: MP4 (.mp4).
- Your files are not uploaded: the work is done in your browser, on your own device.
- File size: up to 2 GB per file (the limit of the browser's WebAssembly memory).
- Needs a current browser (Chrome, Edge, Firefox or Safari) on a computer, tablet or phone; nothing to install.
- Free to use, with no sign-up.
Why compress a video in the browser
Phone videos are large: a minute in 1080p is often 100 to 200 MB, and 4K is two or three times that. That is too much for email, many chat apps, school and job portals, or a website. This compressor encodes the video again with H.264, the codec every device plays, at a quality level you choose, and can lower the resolution to 1080p, 720p or 480p, which saves the most space. The sound is kept as AAC at 128 kbit/s, or removed if you do not need it. Everything happens in your browser tab, so private recordings never leave your computer and there is no upload to wait for. If the result would not be smaller than the original, the tool says so instead of giving you a larger file.
How to compress a video
- Drop the video in the box, or click to choose it.
- Choose how strongly to compress and, if you like, a lower resolution.
- Click Compress video, follow the progress, and save the smaller MP4.
What to know about compressing videos
How long it takes
Video encoding is heavy work, and in the browser it uses one processor core. Expect roughly two to six minutes per minute of 1080p video on a recent laptop, less when you choose 720p, and much more for 4K or on a phone. The page shows the progress and an estimate of the time left; keep the tab open until it is done.
Choosing the settings
Medium compression is a good default: the video looks almost the same and is usually much smaller. For a target size, lower the resolution first: 720p is sharp on phones and laptops and needs about half the data of 1080p. Strong compression gives the smallest file but shows blocky areas in fast movement.
Videos that are already compressed
Videos downloaded from social networks or sent through WhatsApp are already heavily compressed. They may not get much smaller, and the tool will tell you when the result is not smaller than the original.
HDR and 4K iPhone videos
HDR videos are converted to standard 8-bit H.264, so colours can look a little flatter than on the phone. Very long 4K videos may need more memory than the browser allows; lower the resolution or use a desktop program such as HandBrake.
About the formats
MP4
MP4 (MPEG-4 Part 14) is the most common video file format. Phones, cameras, YouTube, WhatsApp and every computer and TV use it. An MP4 is a container: the picture inside is usually compressed with H.264 or H.265 (HEVC) and the sound with AAC, and the same file can also hold subtitles, chapters and a cover image.
- The format was standardised in 2003 and is based on Apple's QuickTime format, which is why MP4 and MOV files are so alike.
- H.264 video with AAC sound plays on practically every device made in the last 15 years.
- A minute of phone video in 1080p is typically 100–200 MB; in 4K it is often 350–500 MB.
- The "faststart" layout puts the index at the beginning, so a video can start playing before it is fully downloaded.
Frequently asked questions
Is my video uploaded?
No. FFmpeg runs in your browser as WebAssembly and encodes the video on your own device. Only the engine (32 MB) is downloaded once, from the jsDelivr network.
How much smaller will the video get?
It depends on the original. Phone videos often shrink by 60 to 80 percent with medium compression, and even more at 720p. Videos that were compressed before shrink less.
Can I compress a MOV, WebM or MKV video?
Yes. The compressor reads the common video formats and always writes an MP4 with H.264 and AAC, which plays everywhere.
Is there a watermark or a size limit?
There is no watermark. Files up to 2 GB can be opened; the limit in practice is how long you are willing to wait and how much memory your browser has.