BPM & Key Detection

Detect BPM & Musical Key

Upload any audio file to instantly detect its tempo and musical key — entirely in your browser, no upload to any server.

Drop an audio file here to begin

Supports MP3, WAV, FLAC, AAC, OGG and M4A

Your audio never leaves your device. Analysis runs entirely in your browser using the Web Audio API.

BPM detection and key analysis complete in seconds using on-device signal processing.

Works completely offline after the page loads. No server, no account, no file upload needed.

Built for Musicians & Producers

Whether you need to match tempos for a DJ set or identify the key before sampling, get instant answers with no sign-up required.