You buy a track that sounds right, drop it into Rekordbox or Serato, and the BPM or key clashes with the rest of your set. TempoTango is a Chrome extension built for crate-digging DJs that reads BPM and key in about 40 seconds, so every track you add to a setlist actually fits.
BPM and key aren't shown on the page, and uploader tags are unreliable. TempoTango gives you a confident read in under a minute, without leaving the tab.
Click Listen and TempoTango captures a sample, then runs BPM and key detection on-device. The track keeps playing while it listens.
Audio is analyzed in your browser using essentia.js. Nothing is uploaded: not the audio, not the result, not even the track URL.
Each reading comes with its Camelot position alongside the traditional key, so you can match harmonies at a glance.
Tempo detection that knows the difference between 70 and 140. Confidence indicator on every reading, so you know when to trust it.
Install, click, get answers. No signup, no analytics, no telemetry, no third-party services.
Every analysis is saved with its BPM, key, and Camelot position. Tap any track in your history to jump back to where you found it.
Every BPM and key calculation runs in your browser through essentia.js (WebAssembly). TempoTango has no servers, no telemetry, no third-party services. There's nothing to leak because there's nothing being sent.
Soon. We're polishing the Chrome Web Store submission. Check back here, or follow the project repo for updates.
The first 10 analyses are free on every install. After that, a one-time $14.99 unlocks unlimited use. No subscription, no account. See pricing →
Yes. TempoTango is open source under AGPL-3.0 (inherited from essentia.js, the on-device analysis library it builds on).
Not today. TempoTango is SoundCloud only at launch, because that's where most of the crate-digging happens for the DJs we built this for. YouTube, Bandcamp, and Beatport previews are on the roadmap. Spotify and Apple Music are tougher because of DRM on the audio stream, so we can't promise those.
Very accurate for clear, full-mix tracks. TempoTango runs RhythmExtractor2013 for tempo (with octave-confusion correction) and KeyExtractor for key. These are the same algorithms used in research-grade music tools. Each reading shows a confidence indicator so you know when to second-guess it.
No. While TempoTango is listening, the audio is routed through to your speakers so you hear no break in playback.
At launch, Chrome and Chromium-based browsers (Arc, Brave, Edge) only. Firefox support is on the roadmap; Safari is more constrained on extensions and isn't planned yet.
