Skip to content
CSEN

Tempo and key detector for audio recordings

Find out your recording's tempo and key

Upload a song and within moments you will know its estimated tempo in BPM and its likely key. It comes in handy when you need to quickly check the values for metadata or a release description, or when choosing a remix that matches the right tempo.

The tool works right in your browser – just upload an audio file and wait a few seconds for the result. Supported formats are the common WAV, MP3, FLAC and M4A. For the most accurate estimate, we recommend uploading a song with a distinct rhythm and clear harmony.

  
Click here to upload an audio file
or drag and drop the file here (WAV, MP3, FLAC, M4A)
 
 
  

Your file is not sent anywhere. The whole analysis runs locally on your device – the recording never leaves your browser and we do not store it anywhere. To save time, the tool analyses roughly the first three minutes of the song, which is more than enough for a reliable estimate of both tempo and key.

  

Treat the result as a rough estimate, not the absolute truth. With tempo, so-called half-time or double-time readings can occur (which is why the tool also offers alternatives), and with key, a major key is easily confused with its relative minor. If you know the tempo and key of your song, always go with your own knowledge.

How it works

  
Tempo (BPM): The tool tracks how the energy and the onsets of sounds change over time and looks for a regular rhythmic pulse. From its period, it then calculates the BPM (beats per minute).
  
Key: The tool measures how strongly each pitch is represented in the recording and compares this with typical profiles of major and minor scales. The best-matching key is the resulting estimate.
  
Confidence: For the key, the tool also shows a confidence level and the second most likely estimate – the higher the confidence, the more unambiguous the harmony in the song. The tool does not take key changes into account.

You might also find useful