TempoKey // bpm & key detector

BPM Finder & Song Key Detector

Tap out a rhythm or drop in an audio file — get beats per minute and the musical key instantly. Runs 100% in your browser.

Method 1 · fastest

Tap Tempo

Play your track and tap along with the beat. After 4–6 taps the BPM locks in and gets more accurate with every tap.

Detected BPM
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0 taps
Reset In
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seconds of silence resets
Method 2 · most accurate

Auto-Detect from Audio File

Upload an MP3, WAV or M4A. Your file is analyzed locally on your device — it is never uploaded anywhere.

🎵 Choose or drop an audio file
MP3 · WAV · M4A — processed locally, nothing leaves your device
For DJs

Harmonic Mixing Quick Guide

Once you know your track's Camelot code, mix into these codes for smooth harmonic transitions:

From CamelotMixes perfectly withEnergy shift (+8%)
8A8A · 7A · 9A8B
8B8B · 7B · 9B8A
Any XX (same) · X±1same number, opposite letter
FAQ

Questions about BPM & key detection

How accurate is tap tempo?
With 8+ consistent taps it's typically within ±0.5 BPM — good enough for DJ warm-up planning. For exact values use auto-detect.

Is my music file uploaded to a server?
No. Analysis runs entirely in your browser using the Web Audio API. Nothing is recorded or transmitted.

What is Camelot notation?
A code (like 8A) that makes harmonic mixing easy — adjacent numbers on the camelot wheel sound good together.

Want to go further? Turn your track into a video with our free audio spectrum visualizer.