About BPMKeyFinder
BPMKeyFinder is a free, browser-based tool for detecting BPM (tempo) and musical key from audio files. Built with privacy and accuracy as top priorities for DJs, producers, and music enthusiasts.
Why We Built This
As musicians and developers, we understand the frustration of uploading personal music files to unknown servers—especially unreleased tracks and client work. BPMKeyFinder was built to provide professional-grade audio analysis while keeping your files 100% private. Everything runs locally in your browser, with no uploads, no servers, no data collection.
Technology & Accuracy
Powered by Essentia.js from the Music Technology Group at Universitat Pompeu Fabra, BPMKeyFinder uses the same audio analysis engine trusted by researchers and professionals worldwide. Our BPM detection works reliably across genres from 30-300 BPM, with smart normalization to avoid common half-time/double-time errors. Key detection provides both standard musical notation (C major, A minor) and Camelot Wheel codes for harmonic mixing.
Privacy First, Always
Zero file uploads. Zero tracking. Zero accounts. All audio analysis happens locally in your browser using the Web Audio API and WebAssembly. Your music files never touch our servers—they never even leave your device's memory. We don't collect, store, or transmit any information about your uploads. Not even file names.
Get in Touch
Questions, feedback, or feature requests? Email us at [email protected]. We'd love to hear from you.
Our Mission
BPMKeyFinder is part of our commitment to building privacy-first web tools for the music community. We believe powerful audio analysis should be accessible to everyone—without compromising privacy, requiring subscriptions, or forcing you to trust third-party servers with your creative work.