Key, Camelot code and BPM for any track in your library — plus exactly which keys mix with it. No account, no ads, no upload queue.
MP3 · FLAC · WAV · AAC/M4A · anything your browser can play
Everything runs in your browser. The track is decoded and analysed by your own machine using the Web Audio API — nothing is uploaded, logged or stored. Close the tab and it's gone.
Tempo comes from onset detection and autocorrelation over the strongest minute of the track. On steady electronic music it's reliable; on live drummers or half-time tracks, check the alternative reading shown under the number.
Key comes from a chromagram matched against Krumhansl key profiles — the standard academic method. It's right most of the time, but no key detector is perfect (rekordbox and Mixed In Key disagree with each other constantly). The confidence label tells you how sure it is; if it says low, trust your ears over the badge.
Learn what to actually do with keys in the free harmonic mixing lesson.