Speed and pitch are changed independently in your browser — nothing is uploaded. By default the tempo changes without changing the pitch; raise or lower the pitch separately in semitones. Tick "Link pitch to speed" for the classic faster=higher record effect. WAV is lossless; MP3 is re-encoded with LAME. Input: MP3, WAV, OGG, M4A and more.
An audio speed and pitch changer that lets you change the tempo and pitch of an audio file independently, right in your browser. Drag and drop or choose an MP3, WAV, OGG, M4A or other file (whatever your browser can decode), then use the speed slider to set the tempo from 0.5× to 2× and the pitch slider to shift the pitch in semitones (−12 to +12). By default it time-stretches the audio so you can change the speed without changing the pitch — or shift only the pitch while keeping the same length. Tick "Link pitch to speed" for the classic record / nightcore effect where faster is higher and slower is lower. Presets like "0.75× slower", "1.5× faster" and "Pitch +5 / −5" let you try it instantly. Preview the result, then export as WAV (lossless) or MP3 (128–320 kbps) and download. Great for slowing down or speeding up audio for language learning, transcription and music practice, pitching a voice up or down, or prepping audio for video. Decoding, processing and encoding all happen entirely inside your browser — the file is never uploaded, stored or sent to a server. No install, no sign-up, free to use.
How to use
- Drop an audio file (MP3 / WAV / OGG / M4A and more) or use "choose a file" to load it.
- Set the tempo with the speed slider and the pitch with the pitch slider, independently (or tick "Link pitch to speed" to couple them).
- Hit "Preview" to check it, choose the output format (WAV / MP3) and click "Render & download" to save.
FAQ
Is my audio uploaded?
No. The file you load is decoded, processed and encoded inside your browser — it is never uploaded, stored or sent to a server. Everything runs locally.
Can I change the speed without changing the pitch?
Yes. By default the tool time-stretches the audio so you can change the speed (tempo) while keeping the original pitch. You can also shift only the pitch in semitones while keeping the same length — speed and pitch are set independently.
Can I link speed and pitch for the classic effect?
Yes. Tick "Link pitch to speed" and faster becomes higher while slower becomes lower, like speeding up or slowing down a record, or a nightcore edit.
Which formats can I load, and what can I export?
Input can be MP3, WAV, OGG, M4A and more — whatever your browser can decode. Output can be WAV (lossless) or MP3 (choose 128–320 kbps).
Does big speed or pitch change reduce quality?
Time-stretching uses an overlap-add (WSOLA) method, so larger changes can add some smearing. Within 0.5×–2× and ±12 semitones it aims for quality that works well for language learning, transcription and practice.