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  2. Audio Processing
  3. Audio Speed Changer
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Audio Speed Changer

Speed up or slow down audio playback from 0.25x to 4x without changing pitch. Perfect for transcription, music practice, podcast speed adjustment, and audiobook listening.

Speed up or slow down audio playback without changing pitch, or change both speed and pitch together. Drag the speed slider from 0.25x to 4x and hear the result immediately. Great for transcription work, language study, music practice, or fitting audio into a specific time window.

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Audio Speed Changer: a worked example

A lecture recording is too slow to review and you want 1.5× without chipmunk pitch.

Input

lecture.mp3 · 1.5× · preserve pitch
Audio Speed Changer produces

Output

A 1.5× file at the original pitch, natural voice, shorter runtime

Time-stretching changes duration without resampling, so the pitch stays natural instead of rising like a sped-up tape. Decoupling speed from pitch is exactly what makes faster review listenable.

What is Audio Speed Changer?

Speed up or slow down audio playback without changing pitch, or change both speed and pitch together. Drag the speed slider from 0.25x to 4x and hear the result immediately. Great for transcription work, language study, music practice, or fitting audio into a specific time window.

How to use

  1. 1Upload an audio file
  2. 2Move the speed slider to your target rate
  3. 3Toggle pitch preservation on or off
  4. 4Preview the result, then export

Key features

  • Speed range from 0.25x to 4x
  • Pitch-preserved time stretching
  • Combined speed-and-pitch mode
  • Real-time preview during adjustment
  • Export in MP3, WAV, or OGG

Common use cases

  • Transcription

    Slow down fast speech to catch every word while typing.

  • Language learning

    Reduce playback speed on foreign-language audio to better follow pronunciation.

  • Music practice

    Slow a difficult passage down to practice at a comfortable tempo before building back up.

  • Time fitting

    Speed up a voiceover slightly to fit a fixed video duration without re-recording.

Frequently asked questions

Does changing speed affect pitch?

With pitch preservation enabled, the pitch stays the same regardless of speed. With it disabled, pitch rises when sped up and drops when slowed down, like a tape machine.

Is there quality loss at extreme speeds?

Time-stretching algorithms introduce artifacts at very low or very high ratios. Staying within 0.5x-2x produces the cleanest results.

Can I adjust speed for just part of a file?

This tool applies a uniform speed change. To adjust only a section, trim it first, change speed, then merge it back.

Private by design

Audio is decoded and processed locally with the Web Audio API. Your files are never uploaded to a server.