BPM & Key Finder
DROP A TRACK TO ANALYZE
Tempo, key and harmonic mix suggestions in a few seconds. Audio is parsed in your browser and never uploaded.
MP3 · WAV · FLAC · AAC · OGG / UP TO 50 MB / LOCAL PARSING
Click or drag any audio file into the drop zone.
Tempo, key and confidence are computed on your device.
Read compatible Camelot keys and delay sync values.
ABOUT THIS TOOL
Free Online BPM & Key Finder for DJs and Producers
Detect tempo (BPM), musical key, and Camelot notation from any audio file — entirely in your browser. Built for harmonic mixing prep: find compatible keys and tempos before your next set or production session.
How it works
- 01Upload an audio file (MP3, WAV, FLAC, AAC, OGG) or pick one from Library after sign-in.
- 02Essentia.js analyzes beat onsets and chromagram in WebAssembly — BPM (with half/double toggle) and key appear in seconds.
- 03Use the Camelot mixing guide to plan harmonically compatible transitions with adjacent wheel codes.
Key features
- Browser-local analysis — your audio stays on your device
- BPM detection with half/double tempo correction
- Musical key plus Camelot (Open Key) notation
- Harmonic mixing cheat sheet for DJ transitions
Common questions
Musictool uses Essentia.js — the same MIR algorithms used in research and production tools, compiled to WebAssembly. Most commercial tracks return stable BPM and key; live recordings or heavily processed audio may need manual half/double BPM adjustment.