How to Add Metadata to MP4 Videos
Embed title, description, artist, album, genre, year, and copyright into MP4 video files. iTunes-compatible atoms work in Apple Music, QuickTime, and YouTube.
Open the tool →Why MP4 metadata matters
MP4 is the dominant video container on the web and in most modern apps. Each MP4 supports iTunes-style metadata atoms inside its moov/udta/meta/ilst tree: title (©nam), description (©cmt), artist (©ART), album (©alb), genre (©gen), year (©day), copyright (©cpy + cprt), location (©xyz), keywords (keyw), and rating. Apple Music, QuickTime, VLC, YouTube ingestion, and Premiere Pro all read these atoms when present.
How MP4 stores metadata
MP4 files use a hierarchical atom (box) structure. Metadata is stored in the udta atom inside the moov atom, with a meta sub-atom containing an ilst (iTunes list). Each metadata field is an atom whose 4-byte type names the field (©nam = name, ©alb = album, etc.) and whose data sub-atom holds the actual value. MediaMeta writes this exact structure for maximum compatibility with Apple-ecosystem tools.
Step 1 — Open the MP4 editor
Visit /mp4-metadata-editor for single videos, or /bulk-editor for batches. Both tools accept MP4 files up to your browser memory limit (usually 1-2 GB on desktop, less on mobile). All processing happens client-side, so even large videos stay on your machine.
Step 2 — Fill the video-specific defaults
For videos, the most valuable fields are Title, Artist, Album, Genre, Year, and Copyright. Title is the human-friendly name shown by players. Artist is the creator. Album groups related videos (a season, a project). Genre helps category-based browsing in media players. Year and Copyright cover provenance. Use the bulk editor to set these once and apply to a whole series.
Step 3 — Process and download
Click Process. MediaMeta rewrites only the moov atom — the video and audio sample tables, the actual codec bitstreams, and the timing data are untouched. If your moov sits before the mdat (faststart-optimized MP4 — the format YouTube and HLS prefer), sample offsets are automatically re-computed so playback stays intact.
What happens for fragmented MP4s
Some MP4s (DASH, CMAF) are fragmented and use the iso5 or dash brand. These have a different structure that does not support iTunes-style atoms in a single moov. The editor detects these files and returns them unchanged with a warning. If you need metadata in a fragmented MP4, you usually need to re-mux to a non-fragmented variant first.
Verifying MP4 metadata
Drop the processed MP4 into the metadata viewer or open it in QuickTime → Show Inspector. You should see Title, Artist, Album, and the other fields you wrote. ExifTool can also verify the underlying atom structure if you want byte-level confirmation.
MP4 metadata for YouTube and platforms
Most large platforms (YouTube, Vimeo, Twitter) re-encode uploaded videos and strip the original atoms. Their UIs let you fill in title and description after upload, so MP4 atoms are mostly useful for downloads, archives, and platforms that respect them (Apple Music, smaller distribution platforms, in-house DAM systems). For YouTube SEO, focus on the title and description you fill in YouTube Studio after upload.
Privacy: stripping MP4 metadata before sharing
Some MP4s (especially from phones) contain GPS coordinates (©xyz) and device serials. If you do not want this shared, use the metadata remover to strip the entire udta atom before sharing. The remover handles offset shifting automatically.
Frequently asked questions
- Will adding metadata re-encode my video?
- No. MediaMeta only rewrites the metadata atoms — codec streams and audio are untouched. The output is bit-identical to the input except for the new moov header.
- What is the difference between MP4 and MOV metadata?
- MP4 and MOV (Apple QuickTime) share the same atom structure for metadata. MediaMeta currently targets the .mp4 extension; .mov files often work but are not officially supported. Re-mux to .mp4 if you encounter issues.
- Why is my fragmented MP4 returned unchanged?
- Fragmented MP4s (iso5/dash brands) use a different layout where moov-level atoms cannot be re-written safely without breaking playback. MediaMeta returns these files unchanged with a warning instead of corrupting them.
- Are my files uploaded when I edit MP4 metadata?
- No. The MP4 editor runs entirely in your browser. Even large videos never leave your device.
Ready to apply this?
Use MediaMeta's browser-based tools — your files never leave your device.