Are my files uploaded somewhere?

No. Files stay in your browser. Reading, editing, and writing all happen locally with WebCodecs and Mediabunny. Nothing is sent to a server.

Which file formats can I edit?

Video: MP4, MOV, MKV, WebM. Audio: MP3, M4A/AAC, FLAC, WAV, Ogg/Opus. Each container stores metadata in its own way and the editor maps the same fields onto the right tags for each format.

Will editing metadata re-encode the file?

No. By default the editor remuxes the file: original audio and video samples are copied without quality loss. Only the metadata tags and embedded cover art are rewritten.

Why does the output size differ slightly from the original?

Containers store tags, cover art, and indexing tables differently. Adding or removing artwork and tags changes those bytes, but the underlying audio and video data is untouched.

What happens if I leave a field empty?

When 'Overwrite existing metadata' is on, empty fields clear the original value. With it off, empty fields keep what was already in the file so you can edit selectively.

Can I add or change the cover image?

Yes. Upload a JPG, PNG, or WebP. The image is embedded in the file using each format's native cover art tag (ID3 APIC for MP3, MP4 covr atom, FLAC PICTURE block, and so on).

Why does my cover image not show in some apps?

Some players ignore back covers or non-front kinds, and Ogg or WAV may have limited cover art support depending on the player. Use Front cover and a square JPEG for the widest compatibility.

Does the tool work on mobile?

Yes. Modern Chrome, Edge, Safari, and Firefox on iOS, Android, macOS, and Windows are supported. Very large files may run out of browser memory on low-end phones.

Why did my edit fail with an error?

Common reasons are unsupported codecs, corrupted containers, files larger than 2 GB, or DRM-protected media. The error panel shows a specific reason and a recovery hint.

Is the original file changed?

Never. The tool always produces a new file you download. Your source remains untouched on disk.

appkiro.com

Video

媒体元数据编辑

Video

改 MP4、MP3、FLAC 等媒体文件的标题、艺人、专辑、年份、描述、封面——不重新编码,不损失画质音质。

1. Upload Media File

Drop media file here

or click to browse

Supported formats: MP4, MOV, MKV, MP3, M4A, AAC, FLAC

Max file size: 2GB

2. Edit Metadata

Title

Artist

Album / Collection

Year

Description

0 / 500

Cover Image

Embed artwork into file

Save cover image into the media file.

Overwrite existing metadata

Replace existing metadata with new values.

3. Preview

Media preview

Upload a video or audio file to start.

Format

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Resolution

—

Duration

—

File size

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4. Result

Updated file appears here

Result preview

Apply metadata to enable download.

Original file

—

Updated file

—

Difference

—

Format

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Download File

Your files are processed entirely in your browser. Nothing is uploaded to a server, and the original file is never modified.

The Video and Audio Metadata Editor lets you change the descriptive tags inside a media file — title, artist, album, year, description, cover artwork, and more — without re-encoding. The original audio and video samples are copied byte-for-byte to a new file, while the tags are rewritten using each container's native fields. Everything happens in your browser, so the source file never leaves your device.

What it does

Reads existing metadata, lets you change it, and writes a new MP4, MOV, MKV, WebM, MP3, M4A/AAC, FLAC, WAV, or Ogg file. Cover art can be added, replaced, or removed.

Who it helps

Podcasters, musicians, video creators, archivists, librarians, and anyone uploading media to YouTube, Apple Music, Spotify, Plex, Jellyfin, or a personal media server that relies on embedded tags.

When to use it

After exporting from a recorder or DAW, before uploading to a streaming platform, when cleaning up an audiobook or podcast back catalog, or whenever a media library shows missing or wrong tags.

Where processing happens

Locally, in your browser, using WebCodecs and Mediabunny. No server upload, no third-party transcoding, no account required.

Step-by-step

Drop a video or audio file (or click to browse).
The editor reads the file's existing tags and pre-fills the form.
Edit the fields you want to change. Leave the rest alone.
Optional: replace the cover image with a JPG, PNG, or WebP.
Choose whether to overwrite existing tags or only fill in missing ones.
Click Apply Metadata and download the new file.

Field reference

Title: The track or video name shown in players, libraries, and platforms.
Artist: The primary creator. For podcasts, this is usually the host or show.
Album / Collection: The album, season, or series the file belongs to.
Album Artist: The credited artist for the whole collection. Useful for compilations.
Year: Release or recording year. Stored as a date inside the container.
Genre: Free-form category — Documentary, Pop, Lecture, Tutorial, etc.
Track # / Tracks total: Position of this file inside its album, plus the total count.
Disc # / Discs total: For multi-disc releases. Most files leave this empty.
Description: A short summary used by podcast apps and video players.
Comment: Free-form notes such as engineer credits or production notes.
Lyrics / transcript: Full lyrics for music or a transcript for spoken-word media.
Cover image: Embedded artwork. Square JPGs around 1000×1000 px work everywhere.
Cover image type: Front, back, or other. Most players only show front covers.
Embed artwork into file: When off, no cover is written. Useful for stripping artwork.
Overwrite existing metadata: When on, empty form fields clear the original tag. When off, blanks keep the original.

Format-specific notes

MP4 / MOV / M4A: tags written as iTunes-style atoms (covr, ©nam, ©ART, …). Compatible with QuickTime, iTunes, Plex, and most players.
MKV / WebM: Matroska Tags + Attachments. Cover art appears as an attached PNG/JPEG file in players that follow the spec.
MP3: ID3v2 frames including APIC for embedded artwork. Compatible with practically every audio player.
FLAC / Ogg / Opus: Vorbis comment block plus PICTURE for cover art. Works in foobar2000, VLC, and modern hi-fi players.
WAV: Editor uses an ID3 chunk so a richer set of tags survives outside basic INFO LIST.
AAC / ADTS: ID3v2 wrapper, like MP3.

Practical tips

Keep covers under 1 MB and square — many libraries scale them to 600×600.
Use 4-digit years (e.g. 2024). The editor stores Jan 1 of that year.
For podcasts, set Title, Artist, Album, Description, and a square cover.
If a player ignores a field, check whether it expects ID3v1 or a different metadata wrapper. Switching the source format usually fixes that.
Double-clicking Edit Another File resets the form for batch-style edits.

Privacy and safety

No account, no signup, no upload. The browser does the work.
The original file is preserved. The result is always a new download.
Cover images are read into memory only long enough to embed them.
The tool refuses files larger than 2 GB to keep memory pressure manageable on phones and laptops.

媒体元数据编辑

1. Upload Media File

2. Edit Metadata

3. Preview

4. Result

What it does

Who it helps

When to use it

Where processing happens

Step-by-step

Field reference

Format-specific notes

Practical tips

Privacy and safety

Frequently Asked Questions

1. Upload Media File

2. Edit Metadata

3. Preview

4. Result

What it does

Who it helps

When to use it

Where processing happens

Step-by-step

Field reference

Format-specific notes

Practical tips

Privacy and safety

Frequently Asked Questions