What is BPM?
BPM (Beats Per Minute) is the standard measurement of musical tempo. It tells you how many beats occur in one minute of audio. For DJs, knowing the exact BPM of a track is essential for beatmatching — synchronizing two tracks so their beats align perfectly during a mix.
How BPM Detection Works
Our algorithm uses a professional multi-stage pipeline:
- 1.
Band-pass filter (50–150 Hz): Isolates kick drum frequencies for cleaner onset detection.
- 2.
Spectral flux onset detection: Identifies transients and beat events across the signal.
- 3.
Multi-segment autocorrelation: Analyzes 4 separate segments and votes for the most consistent BPM.
- 4.
DJ range normalization: Normalizes result to 70–180 BPM, handling half-time and double-time.
FAQ
How accurate is the BPM detection?
Our algorithm uses multi-segment autocorrelation with band-pass filtering focused on kick drum frequencies (50–150 Hz). Accuracy is typically 95%+ for electronic music and 85–90% for complex genres.
What audio formats are supported?
MP3, WAV, FLAC, OGG, M4A, AAC, and OPUS. Files are processed entirely in your browser — nothing is uploaded.
Why does the confidence score matter?
A high confidence (75%+) means the algorithm found a clear, consistent beat. Low confidence may indicate ambient music, complex polyrhythms, or a very short file.
How long does analysis take?
Usually 5–15 seconds. The engine analyzes the first 90 seconds of audio for speed and accuracy.