Speed Up or Slow Down Audio Instantly
Need to speed up a lecture, slow down an interview, or preview music at a different tempo? The Audio Speed Changer lets you adjust the playback speed of your audio file quickly and export the modified version — all within your browser. No uploads, no waits, and your original file stays private on your device.
When To Use Audio Speed Changer
This tool is perfect for students who want to speed through recorded lectures, transcribers who want to slow down speech for greater accuracy, podcasters previewing segments, and musicians testing tempo variations. It's also useful for content producers who need shorter previews of long audio files or need to create audio snippets at different playback speeds.
How It Works
After uploading, you can preview audio directly at the selected speed using the player controls. When you click Apply & Export, the tool renders the speed-changed audio using an offline audio renderer so you get a downloadable file matching the selected speed. For simplicity and broad browser support this tool uses playback-rate-based rendering (which changes pitch along with speed). If you require professional pitch-preserving time-stretching, consider server-side processing with dedicated libraries (e.g., soundtouch, Rubber Band) or DAW software.
Best Practices
Choose a speed that balances comprehension and length. For spoken word, 1.25x to 1.75x often speeds listening without losing clarity. For music, changing speed will affect pitch — test small changes first. Keep an original backup before exporting if you need the unmodified, full-quality source later.
Compatibility & Limitations
Most modern browsers support the Web Audio API used by this tool. Export behavior may vary slightly by browser and codec availability; exported file format is WebM or WAV depending on browser MediaRecorder support and fallback. Very large files may take longer to render depending on device CPU.
Start by uploading your file above, choose a playback speed, preview it, and export the final audio to download. Fast, private, and simple.