Why Change Audio Speed?

• Speed up lectures/podcasts: 1.5× speed to consume content faster
• Slow down music: 0.75× speed to hear details and learn riffs
• Video sync: Match audio duration to video length
• Accessibility: Slow down speech for language learners

Speed Change vs Pitch Change

Simple speed change also changes pitch (faster = higher pitch, slower = lower). Modern time-stretching algorithms (like those using the WSOLA or phase vocoder method) can change speed while keeping the pitch stable — or change both independently.

Step-by-Step: Change Audio Speed Online

1. Open Audio Speed Changer.
2. Upload your audio file.
3. Set the speed multiplier: 0.5× = half speed, 2× = double speed.
4. Enable pitch lock if you want to preserve the original pitch at the new speed.
5. Preview and download.

Practical Speed Recommendations

• 1.25× — barely noticeable, good starting point
• 1.5× — noticeably faster, still natural for speech
• 2× — fast but understandable for familiar content
• 0.75× — good for studying complex material