I’m Andriy, the owner of Pitch Tempo. It’s a free browser tool for musicians who need a different key or speed from an audio file. Upload a file up to 5 minutes and 100 MB, estimate its key/BPM, or change pitch and tempo independently. Tempo runs from 50–150%; pitch spans −12 to +12 semitones. For example, set a 120 BPM practice track to 75% for 90 BPM without changing its key. Preview the first 20 seconds before exporting the full file. Guests can try it without an account; audio processing takes place on our server.