Audio Speed Changer
Change audio playback speed (0.25× to 4.0×) with optional pitch preservation. Drag-and-drop or pick a file, decode with Web Audio API, choose a speed preset (7 from 0.5× to 2.0×) or enter a custom factor, toggle pitch preservation (uses OfflineAudioContext resampling to keep pitch when speed changes), and re-encode as a 16-bit PCM WAV. Pure-JS linear-interpolation resampler, pitch-shift (semitone) calculator, duration & file-size estimator, click-preventing fade in/out, audio preview before/after, history (localStorage), shareable URL, summary stats. 100% client-side.
Change audio playback speed (0.25× to 4.0×) with optional pitch preservation. Drag-and-drop or pick a file, decode with Web Audio API, choose a speed preset (7 from 0.5× to 2.0×) or enter a custom factor, toggle pitch preservation (uses OfflineAudioContext resampling to keep pitch when speed changes), and re-encode as a 16-bit PCM WAV. Pure-JS linear-interpolation resampler, pitch-shift (semitone) calculator, duration & file-size estimator, click-preventing fade in/out, audio preview before/after, history (localStorage), shareable URL, summary stats. 100% client-side. Everything runs locally in your browser — your data never leaves your device.
How to use
- Enter your input in the tool above.
- Adjust any options to your preference.
- Use the Copy or Download buttons to save the result.
- Everything happens locally — your data never leaves your browser.