What is MP4?
A plain-English definition, and the tools that work with it.
MP4 is the most widely supported video format, a container that holds video and audio together. Because virtually every device, editor, browser and platform plays MP4, it's the safe default for sharing, uploading and playing video anywhere.
- If a video won't play or upload, converting it to MP4 usually fixes it, because compatibility is MP4's strength.
- MP4 is a container. The video inside is typically H.264, which balances quality and file size well.
- iPhones often record MOV (sometimes HEVC), which some devices can't play: converting to MP4 solves that.
Tools for MP4
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Video Converter
Convert video between MP4, WebM, MOV, AVI, MKV and GIF in your browser with FFmpeg. Pick a target format, tune MP4 quality, preview the result and download. Nothing is uploaded.
Video Compressor
Compress video in your browser with FFmpeg, shrink MP4, MOV, WebM and MKV files with a simple quality slider, see the exact bytes and percentage saved next to a live preview, then download. Nothing is uploaded.
MOV to MP4
Convert MOV (QuickTime) to MP4 in your browser, a universally compatible H.264/AAC file that plays and uploads everywhere. Real FFmpeg transcoding, in-page preview, one-click download. Nothing is uploaded.
WebM to MP4
Convert WebM to MP4 (H.264) in your browser, the universally compatible format that plays on iPhones, in editors and on social. Preview the result and download. Nothing is uploaded.
MP4 problems we solve
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Frequently asked questions
Related terms
- GIFA GIF (Graphics Interchange Format) is an image format best known for short, silent, looping animations. It's limited to 256 colors, which keeps simple loops small but makes it a poor choice for detailed video or photographs.
- BitrateBitrate is how much data is used per second of audio or video, measured in kbps or Mbps. A higher bitrate means more detail and a larger file. A lower bitrate means a smaller file with more compression. It's the main dial for the quality-versus-size trade-off.
- MP3MP3 is the most universal audio format. It uses lossy compression to shrink sound files to a fraction of their original size with little audible difference, which is why it plays on virtually every device, player and phone.
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