Video format · .mp4
MP4: what it’s for
MP4 (usually H.264 video with AAC audio) is the universal video container: phones, browsers, editors, TVs, and every social platform accept it. When in doubt about compatibility, MP4 is the answer — convert exotic formats into MP4 for sharing and archiving.
Strengths
- Plays on every device, browser, editor, and social platform
- Excellent size-to-quality ratio for H.264-encoded video
- Streams progressively — playback starts before the download finishes
- Our FFmpeg-based tools transcode MP4 locally with real re-encoding
Honest limits
- H.264 is lossy — each transcode generation sheds a little detail
- Large 4K files transcode slowly, especially on phones; be patient or use a desktop
- MP4 cannot carry transparency — use WebM with alpha for overlays
- HDR and 10-bit support in MP4 is patchy across players
Free MP4 tools
Every tool runs in your browser — files never leave your device. Badges say exactly what each tool does with MP4.
- MP4 to MKV ConverterReads MP4
- MP4 to MP3 ConverterReads MP4
- Video to GIFReads MP4
- Video Format ConverterReads + writes MP4
- Video CompressorReads + writes MP4
MP4 FAQs
How do I make an MP4 file smaller?
Use the video compressor to re-encode at a lower bitrate or resolution. Expect roughly half the size with barely visible difference for typical phone footage.
Can I extract audio from an MP4?
Yes — MP4 to MP3 pulls the audio track out locally via FFmpeg, and video-to-GIF turns a clip into a silent looping animation.
Why is MP4 conversion slow on my phone?
Video transcoding is genuinely heavy computation running in your browser. Short clips convert in seconds; long or 4K files can take minutes — desktop browsers are much faster.
Does video conversion upload my footage?
No. FFmpeg runs locally in your browser via WebAssembly. Your video never leaves your device.