Free is enough for most one-off jobs. Pro raises the file and batch caps; Pro + Media unlocks GB-scale streaming and unlimited duration.
Larger files supported on Developer (5 GB CSV) and Enterprise (unlimited). All processing happens in your browser — files never reach a server.
Drop your audio file
JAD runs energy-based onset detection and autocorrelation
See detected BPM and confidence score
0 bytes uploaded. BPM Finder runs entirely in your browser using FFmpeg.wasm 8.1, RNNoise, and the Web Audio API. Your audio stays on your device at all times. No data is sent to any server — critical for sensitive interviews and confidential calls.
For typical 4/4 music with a clear kick: ±1 BPM. For complex polyrhythmic or rubato music, you may need to verify by ear.
A 4-minute song typically resolves in under 2 seconds on a modern laptop. The pipeline downsamples to 11.025 kHz mono before analysis to keep CPU work bounded regardless of source quality.
Generate a static spectrogram from any audio file. Radix-2 FFT with a Hann window and a viridis colour map — runs locally in your browser.
Open toolAdjust playback tempo by percentage. Like time-stretch but expressed as a tempo % — natural for musicians.
Open toolRender a waveform image at any size and color. Perfect for podcast cover art, social posts, or audiograms.
Open tool