Check the pulse
Compare rounded BPM with exact, half-time and double-time.
Private · browser-based audio analysis
Free Tempo & Key Finder
Unlimited runsNo signupAudio stays on your device
Automatically detect the BPM, tempo, musical key and Camelot code of a song directly in your browser.
Local audio analyzer
Find BPM & key for free
Audio is decoded and analyzed in this browser. Filenames, PCM and results are never sent to our server.
Read the result
More useful than a single BPM or key
The main estimate comes with alternate rhythm and harmonic context, so you can compare the output with what you hear.
Check the harmony
Review the key, mode and possible alternative by ear.
Plan the next step
Use relative and Camelot keys as options to audition, not rules.
Results are best-effort estimates. Rhythm ambiguity, modulation, percussion, speech and noise can produce plausible but incorrect values. Check the result by ear when it matters.
One analysis, useful rhythmic context
The BPM result includes a rounded value for quick reference and a decimal estimate for more precise timing. Half-time and double-time values make alternate pulse interpretations visible, while milliseconds per beat provides a practical timing conversion.
If you can hear the pulse but do not have a file, the Tap Tempo tool calculates a manual rolling BPM from mouse, touch or Space-key input.
Key, Camelot and harmonic relationships
The key result combines a tonic with major or minor mode, maps it to Camelot notation and shows the relative key. When a second harmonic profile disagrees, it appears as a possible alternative rather than being hidden.
Use the Camelot Wheel to explore compatible keys or the Key Transposer to calculate a semitone change. These references support musical judgment; they do not guarantee that two recordings will mix well.
Useful for listening, sorting and preparation
- DJs
- Compare tempo and harmonic context before auditioning a mix.
- Musicians
- Find a starting estimate before checking the song by ear.
- Producers
- Review BPM, key and timing context for a local reference.
- Teachers and students
- Connect keys with relative and Camelot relationships.
How accurate are the BPM and key results?
They are best-effort estimates. The analyzer follows an always-output approach after successful analysis, so half/double-time rhythm, tempo drift, modulation, relative keys, percussion, speech and noise can all produce plausible but incorrect values. The current calibration did not meet the project’s strict accuracy thresholds, and no blind-validated accuracy claim is made.
Read the measured accuracy report before relying on a result for an important decision.