Format at a glance
- Full name
- MPEG-4 Video File
- File extensions
- .m4v
- MIME types
- video/x-m4v
- Category
- Video
- Compression
- Depends on the contained codec
- Transparency
- Not applicable
- Animation
- Not applicable
- Properties
- Multiple media tracks, Subtitles, Chapters
Suitable tools
What is this format?
M4V is based on the ISO Base Media File Format and organizes video, audio and metadata tracks in boxes. The extension often distinguishes video from audio-only M4A files.
Some M4V files obtained through Apple services may be DRM-protected. Normal container conversion cannot and must not remove or bypass that protection.
What is it used for?
- Video in Apple media libraries
- Movies and television in compatible workflows
- MPEG-4 video using H.264 or HEVC
- Exchange between Apple and general video software
Which programs can open it?
- QuickTime Player and Apple TV
- VLC and mpv
- FFmpeg and video converters
- Editors with MPEG-4 import
Support across devices and browsers
VLC, mpv and matching system codecs play M4V; the contained codecs determine compatibility.
QuickTime supports selected combinations, while VLC and FFmpeg cover additional M4V variants.
VLC, mpv and FFmpeg handle many M4V codec combinations.
Playback and hardware decoding depend on the device and contained codecs.
Apple devices primarily support common H.264, HEVC and AAC combinations.
The container alone is insufficient: the browser must support every contained video and audio codec.
Advantages
- Closely related to the widely used MP4 container
- Supports efficient modern video and audio codecs
- Good compatibility in the Apple ecosystem
Disadvantages
- DRM-protected files cannot be freely converted
- .mp4 is more commonly expected outside Apple workflows
- Playback still depends on contained codecs
Comparison with alternatives
MP4 and M4V use closely related structures; MP4 is the more universal general-purpose extension.
MOV is more closely tied to QuickTime and production workflows and can carry additional professional codecs.
WebM uses open web-oriented codecs, while M4V commonly uses H.264/HEVC and AAC.
LocalFileLab support
M4V is recognized as an input. Containers and media streams are read locally depending on their codecs.
M4V is available as a local output; available settings depend on the format.
LocalFileLab can compress M4V locally or package it in a supported archive; already compressed content will not necessarily become smaller.
A local preview is available when the browser can display or play the content.
Existing metadata can be retained or removed depending on the selected path.
Container and codecs
The LocalFileLab statements below come from the FFmpeg/WASM and WebCodecs paths actually configured in the repository. Decoders or tracks not explicitly evidenced in code are marked unverified.
- Container
- M4V / ISO Base Media File Format
- Typical video codecs
- H.264 / AVC, H.265 / HEVC, MPEG-4 Part 2
- Typical audio codecs
- AAC, ALAC
| Codec | Type | Input | Output | Notes |
|---|---|---|---|---|
| H.264 / AVC | Video | Unverified | Supported | The project does not enumerate the FFmpeg/WASM input decoder per codec. A concrete FFmpeg/WASM encoder is configured in the repository. |
| H.265 / HEVC | Video | Unverified | Supported | The project does not enumerate the FFmpeg/WASM input decoder per codec. A concrete FFmpeg/WASM encoder is configured in the repository. Playback may require a matching browser or system codec. |
| MPEG-4 Part 2 | Video | Unverified | Supported | The project does not enumerate the FFmpeg/WASM input decoder per codec. A concrete FFmpeg/WASM encoder is configured in the repository. |
| AAC | Audio | Unverified | Supported | The project does not enumerate the FFmpeg/WASM input decoder per codec. A concrete FFmpeg/WASM encoder is configured in the repository. |
| ALAC | Audio | Unverified | Supported | The project does not enumerate the FFmpeg/WASM input decoder per codec. A concrete FFmpeg/WASM encoder is configured in the repository. |
| Text and subtitle tracks | Subtitle | Unverified | Not supported | This track is not mapped explicitly during export. |
Tracks and metadata
- Subtitle tracks
- Unverified
- Multiple audio tracks
- Not supported
- Chapters
- Unverified
- Metadata
- Configurable
Known combinations
A concrete FFmpeg/WASM encoder is configured in the repository.
A concrete FFmpeg/WASM encoder is configured in the repository. Playback may require a matching browser or system codec.
Related formats
Frequently asked questions
Can M4V simply be renamed to MP4?
Playback may work for an unprotected compatible file, but actual inspection or remuxing is more reliable.
Is every M4V file protected?
No. M4V may be an ordinary unprotected MPEG-4 video; only some distribution-service content uses DRM.
Which codecs are typical in M4V?
H.264/AVC with AAC is common. HEVC, MPEG-4 Part 2 and ALAC are also possible, with device-dependent support.