Convert MP3 to JSON Online Free
Extract the technical metadata and ID3 tag data of any MP3 file as structured JSON — title, artist, album, bitrate, sample rate, duration, and stream details. Powered by ffprobe.
By ChangeThisFile Team · Last updated: March 2026
ChangeThisFile extracts metadata from your MP3 file as structured JSON using ffprobe on a secure server. The output includes ID3 tags (title, artist, album), bitrate, sample rate, duration, channel count, and codec details. Your file is auto-deleted after conversion. Free, no signup required.
Convert MP3 to JSON
Drop your MP3 file here to convert it instantly
Drag & drop your .mp3 file here, or click to browse
Convert to JSON instantly
MP3 vs JSON: Format Comparison
Key differences between the two formats
| Feature | MP3 | JSON |
|---|---|---|
| Type | Binary audio container with ID3 metadata | Plain-text structured data |
| Purpose | Store compressed audio with embedded tags | Describe key/value hierarchies |
| Human-readable | No — binary payload | Yes — opens in any text editor |
| Contains | MPEG audio frames, ID3v1/ID3v2 tags, optional cover art | Strings, numbers, arrays, nested objects |
| File size | Several MB per song | A few KB of metadata |
| Use case | Music playback and distribution | Library indexing and tagging workflows |
| Compatible with | Every media player and device | Every programming language |
When to Convert
Common scenarios where this conversion is useful
Bulk-tag a music library
Export the ID3 metadata of an entire MP3 collection to JSON, edit it in a spreadsheet or script, and re-import — much faster than clicking through a tag editor song by song.
Validate podcast deliveries
Confirm an MP3 episode meets a podcast network's spec — 44.1 kHz, stereo, 128 kbps or higher — by inspecting the JSON before uploading.
Build a searchable audio archive
Pipe MP3 metadata into a database to power search and filtering by artist, album, year, or duration without scanning the audio every time.
Verify download integrity and tagging
After downloading or transferring MP3 files, confirm the bitrate, sample rate, and tag completeness against a manifest using the JSON output.
Diagnose audio quality issues
Inspect the codec profile and bitrate of an MP3 to find out whether it was re-encoded from a lower-quality source or transcoded multiple times.
Who Uses This Conversion
Tailored guidance for different workflows
For Podcasters
- Audit a season of episodes for consistent bitrate, sample rate, and channel count using JSON exports
- Confirm every episode has the required ID3 tags (title, episode number, season, podcast name) before submitting to directories
- Verify intro/outro music is tagged correctly for licensing reports
For Music Librarians
- Build a catalogue spreadsheet by extracting ID3 tags from thousands of MP3 files via the JSON output
- Detect missing or inconsistent tags across an archive before importing into a media server like Plex or Jellyfin
For Developers
- Power a music app's metadata API by serving the same JSON shape that ffprobe produces
- Validate user uploads server-side by parsing the JSON and rejecting files outside accepted bitrate or sample-rate ranges
How to Convert MP3 to JSON
-
1
Upload your MP3 file
Drag and drop your .mp3 file onto the converter, or click to browse. Files up to 500MB are supported.
-
2
Server-side metadata extraction
Your file is uploaded over an encrypted connection and inspected with ffprobe. ID3 tags, codec, bitrate, duration, and sample rate are serialised as JSON.
-
3
Download the JSON
Click Download to save the resulting .json file. Your original MP3 is automatically deleted from our servers after processing.
Frequently Asked Questions
No. Audio waveform data cannot be meaningfully expressed as JSON. This tool extracts metadata — ID3 tags, bitrate, sample rate, channel count, duration, and codec. If you want a different audio format, try MP3 to WAV or MP3 to FLAC.
ffprobe reads both ID3v1 and ID3v2 tags, including extended ID3v2.3 and ID3v2.4 frames. All recognised tags appear under the format.tags object in the JSON output.
Embedded album art is detected and listed as an attached_pic stream, but the image bytes themselves are not inlined into the JSON. Use the MP3 to JPG or MP3 to PNG converter if you want to extract the artwork.
Yes. ChangeThisFile is completely free with no signup, no usage limits, and no watermark.
Yes. Your MP3 is transferred over HTTPS and automatically deleted from our servers immediately after the JSON is produced.
The JSON has two top-level objects: 'format' (container info, duration, bit_rate, and a 'tags' object with ID3 values) and 'streams' (an array describing each audio stream). This matches the standard ffprobe -show_format -show_streams JSON schema.
Yes. The output is plain JSON. Use JSON.parse() in JavaScript, json.load() in Python, or any JSON parser in your language of choice.
Yes. ffprobe reports the average and overall bitrate, and you can detect VBR by the difference between bit_rate and the stream-level bit_rate. The codec_long_name will also show 'MP3 (MPEG audio layer 3)' with frame layout details.
Yes. The converter runs in any modern mobile browser. Upload an MP3 from your device and download the JSON directly.
If ffprobe can't parse the file, the converter returns an error rather than partial metadata. Re-export from your editor or DAW and try again.
Related Conversions
Related Tools
Free tools to edit, optimize, and manage your files.
Need to convert programmatically?
Use the ChangeThisFile API to convert MP3 to JSON in your app. No rate limits, up to 500MB files, simple REST endpoint.
Ready to convert your file?
Convert MP3 to JSON instantly — free, no signup required.
Start Converting