offlinewebtools.com browser-local workbench

Audio Time Stretch

Change audio playback speed without affecting pitch. Perfect for learning music, creating slow-motion effects, or speeding up audiobooks while maintaining natural sound.

Shipped
Browser local

Files are processed locally in your browser using WebAssembly. This input is required.

Saved FFmpeg presets (stored locally)

Preview and export

Inspect the source before running FFmpeg, then preview the generated output before downloading.

Local media
Choose a media file to fill this source preview before processing.

Expected output

The generated file preview, size, type, and download action appear here after processing.

Playback speed multiplier (0.25x = 4× slower, 2.0x = 2× faster, 1.0x = original speed)

Use Cases

  • • 0.5x-0.75x: Learning music, transcription, practice
  • • 1.1x-1.25x: Faster audiobook listening
  • • 1.5x-2.0x: Quick content review, efficient consumption
  • • 2.0x+: Creative effects, time-lapse audio

What this tool does

Audio Time Stretch helps you change audio playback speed without affecting pitch. Perfect for learning music, creating slow-motion effects, or speeding up audiobooks while maintaining natural sound.

What you get

Audio Time Stretch produces a direct output in this page and keeps all processing on your device, with nothing uploaded to our servers.

Report a bug

If this tool misbehaves, share a quick summary so we can investigate. We include the tool URL automatically—no need to copy and paste.