BPM Auto-Tagger
Detect the tempo of an MP3 and write it into the file's ID3 BPM tag automatically.
Drop your audio file here
or click to browse a file
MP3 only — this tool writes ID3v2 BPM tags.
About this BPM auto-tagger
DJ software (Rekordbox, Serato, Traktor, Mixxx) reads BPM tags from MP3 ID3 metadata to organise libraries by tempo. If your tracks don't have BPM tags, you have to manually set them — tedious for a 1000-track library.
This tool combines our BPM detector with our ID3 writer: drop in an MP3, the tool detects the tempo and writes it back into the file's ID3 tag in one step. Output is the same MP3 with the BPM tag added (or updated).
How to auto-tag BPM
- 01
Drop in an MP3
Tool detects the BPM with onset analysis.
- 02
Review the detected BPM
Confirm it looks right, or override manually if it picked half/double.
- 03
Download tagged MP3
Same audio, BPM written into the ID3 TBPM frame.
Why use the BPM auto-tagger
- Combines BPM detection + ID3 tag writing in one step
- Audio is bit-identical — only metadata changes
- Manual override for half/double-time mistakes
- Output works in Rekordbox, Serato, Traktor, Mixxx, iTunes, Foobar2000
- Free, private, no install
- No watermark, no signup
BPM auto-tagger FAQ
What ID3 frame is the BPM stored in?
TBPM (text frame, BPM as integer string). Standard since ID3v2.3, supported by every modern DJ tool and music player.
Will the audio be re-encoded?
No — only the metadata frames are changed. Audio is preserved bit-for-bit.
What if the detected BPM is wrong?
Click the half-time or double-time alternative, or type the correct BPM manually before tagging.
Is my file kept private?
Yes. We don't analyse or index your file beyond detecting and writing the BPM tag.
More dj & mix tools
Mashups, BPM, multi-track sets