MP4 (MPEG-4 Part 14)
MP4 is the most widely supported video format, usually holding H.264 or H.265 video and AAC audio. Learn how MP4 works and how to reduce its size.
- Type
- Video
- File extensions
- .mp4, .m4v
- MIME type
- video/mp4
What is MP4?
MP4 is a container: it holds video, audio, subtitles and metadata in one file. Most MP4 files contain H.264 (AVC) video and AAC audio, a combination that plays on almost every device; newer files may use H.265 (HEVC) or AV1.
File size depends mainly on resolution, duration and bitrate. Lowering the resolution or using a higher compression level is the most effective way to shrink an MP4.
When to use MP4
- Sharing video on any device or platform
- Uploading to social networks and video sites
- Web video with the HTML video element
Limitations
- H.264 is less efficient than newer codecs such as AV1
- Editing and re-saving with lossy codecs reduces quality each time
Compatibility
Plays in every modern browser, phone, TV and video editor when it uses H.264 and AAC.
Compared with other formats
Tools for MP4 files
Video to GIF
Turn a section of an MP4, WebM or MOV video into a high-quality animated GIF using a generated palette.
Video Converter
Convert videos between MP4, WebM, MOV and MKV with codec and quality options.
Video Cutter
Remove an unwanted section from the middle of a video and join the remaining parts.
Video Trimmer
Keep only the part of a video between a start and end time.
Video Merger
Join multiple video clips into a single MP4 in the order you choose.
Video Compressor
Reduce video file size with quality-based or target-size compression.
Video Resizer
Change video resolution, for example from 4K to 1080p or 720p.
Video Cropper
Crop the video frame to a region or aspect ratio such as 9:16 for vertical video.
Video Rotator
Fix sideways or upside-down videos by rotating them 90, 180 or 270 degrees.
Video Reverser
Play a short video clip backwards, with or without reversed audio.
Video to MP3
Extract the audio track from any video and save it as an MP3.
Video to WebM
Convert videos to WebM (VP9/Opus) for open, web-friendly playback.
Convert other files to MP4
GIF to MP4
Convert an animated GIF into a much smaller H.264 MP4 video suitable for the web and social media.
WebM to MP4
Convert WebM recordings to H.264 MP4 for playback on any device.
MOV to MP4
Convert QuickTime MOV videos from iPhones and cameras to MP4.
MKV to MP4
Convert or remux MKV files to MP4 for broader device support.