Trying a different tempo when you only have the audio sketch

If you still have the notation or DAW project, changing the tempo there is usually the cleanest option. But sometimes all you have handy is a short audio render and you want to hear whether the idea feels better a little slower.

I own Pitch Tempo, a free tool at https://pitch-tempo.online/ that can make that sort of listening copy. Here is a simple example:

1. Start with your own audio file, or one you have permission to upload and edit.

2. For a steady 100 BPM sketch you want to hear at 90 BPM, set tempo to 90%. Leave pitch at 0 semitones to keep the key. The calculation is target BPM / original BPM × 100.

3. Listen to the preview before exporting. Check the attacks and sustained notes: slower is useful only if the result still lets you judge the music.

4. Export the full file and save it. If you like the new pacing, you can go back to the source project when it is available and make the actual compositional changes there.

This stretches the entire recording by one ratio. It will not rewrite tempo markings, remove rubato, turn audio into notation or MIDI, or change just one instrument in a mix.

Files can be up to five minutes and 100 MB. Tempo runs from 50% to 150%, independently of pitch. The preview covers the first 20 seconds of the source, so listen through the export too. A full export finishes that editing session; another version needs a new upload. Guests get three uploads per rolling 24 hours. Processing is on our server and guest audio expires 24 hours after the original upload, so keep your original and download the copy you want.

Happy to answer questions about whether a particular file-based task fits those limits.