Measure the tempo and the musical key of a song on your own device, with the Camelot code DJs mix by. When a song could honestly be read two ways (72 or 144 BPM, C major or A minor) the page shows both, instead of picking one and hiding the doubt.
How it works
- Drop one song or a whole folder of them.
- Each one is analysed in your browser: tempo first, then key.
- Read the results, or download them as a spreadsheet (CSV) for a whole set.
Questions
- Does my file get uploaded?
- No. The models and all processing run inside your browser on your own device. You can verify this yourself: open your browser’s DevTools, watch the Network tab, and process a file: there are no uploads. After the first visit most tools also work fully offline.
- Why does it show two tempos?
- Because both are often right. A song at 72 BPM has a strong pulse at 144 too, and which one you call the tempo depends on whether you count the half-time feel. The first number is the best guess; the second is the one a DJ software might show instead.
- Why is the key sometimes major or minor?
- A major key and its relative minor (C major and A minor) use exactly the same notes, so a song that sits between them can be read either way. They share a Camelot number (8B and 8A), which is why they mix together anyway.
- How much of the song does it listen to?
- Up to 90 seconds from the middle, where the groove and the harmony are most settled. Intros and outros often have no drums or an unstable key, and skipping them makes the answer better, not worse.