TempoTango reads the tempo and musical key of whatever's playing in your active tab. Built for DJs digging on SoundCloud — check a track before you buy it, in about 40 seconds.
SoundCloud doesn't show BPM or key, and uploader tags are unreliable. TempoTango gives you a confident read in under a minute — without leaving the page.
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.
Works on private uploads, demos, and unreleased gems — anything that plays in the tab. No catalog lookup, no fingerprinting.
Browse, queue, or hit play on anything you'd normally listen to.
Open the popup and hit the big Listen button. The track keeps playing.
About 40 seconds later you have everything you need to decide.
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. Drop your email above and you'll be the first to know when it's live — no other emails, ever.
No. TempoTango will be free at launch, with no account required and no upsells. It's open source under AGPL-3.0 (inherited from essentia.js).
At launch, SoundCloud only — that's where most of the crate-digging happens. Bandcamp, YouTube, and Beatport previews are on the roadmap.
Very accurate for clear, full-mix tracks. TempoTango runs RhythmExtractor2013 for tempo (with octave-confusion correction) and KeyExtractor for key — 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.
One email when TempoTango lands in the Chrome Web Store. That's it.