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Audio Speed Changer

Change the playback speed and tempo of audio files

Upload Audio File

Supports MP3, WAV, OGG, FLAC, AAC, M4A

How to Use

1

Upload Your File

Drag and drop your file or click to browse. Your file stays in your browser.

2

Adjust Settings

Configure options to get exactly the result you need.

3

Download Result

Process and download your file instantly — no waiting, no server upload.

Why Use This Tool

100% Free

No hidden costs, no premium tiers — every feature is free.

No Installation

Runs entirely in your browser. No software to download or install.

Private & Secure

Your data never leaves your device. Nothing is uploaded to any server.

Works on Mobile

Fully responsive — use on your phone, tablet, or desktop.

Your Files Stay Private

This tool processes your files entirely in your browser. Nothing is uploaded to any server — your data never leaves your device.

  • No server upload — 100% client-side processing
  • No data stored — files are discarded when you close the tab
  • No account required — use instantly without signing up
Multimedia Guide

How Audio Speed and Pitch Shifting Work

Key Takeaways

  • Time-stretching changes speed without altering pitch, unlike simple resampling which affects both.
  • Common ranges are 0.5x (half speed) to 2.0x (double speed) for practical listening.
  • The Web Audio API's playbackRate property enables real-time speed changes directly in the browser.

Changing audio playback speed is useful for studying, transcription, music practice, and content consumption. Modern time-stretching algorithms can speed up or slow down audio while preserving the original pitch, so voices sound natural even at 1.5x speed. This tool processes your audio files entirely in your browser.

1.5×

Optimal study speed

Common Use Cases

1

Podcast & Audiobook Speed Listening

Listen at 1.25x–1.5x speed to consume more content in less time without losing comprehension.

2

Music Transcription

Slow down complex passages to 0.5x or 0.75x to hear and transcribe individual notes and chord voicings.

3

Language Learning

Slow native speaker audio to catch pronunciation details, then gradually increase speed as listening skills improve.

4

Dance & Choreography

Slow down music to learn complex choreography step by step, then bring it back to full speed as the routine becomes comfortable.

Speed Adjustment Tips

Start with small increments (1.1x, 1.25x) for spoken content. Jumping to 2x drops comprehension significantly.

For transcription, 0.75x is often the sweet spot — slow enough to hear details but fast enough to maintain context.

Export the adjusted file if you want to transfer it to a device that doesn't support variable playback speed.

Pitch-preserved speed change (time stretching) sounds more natural than simple resampling, especially for speech.

All audio processing is performed entirely in your browser. No audio files are uploaded or transmitted to any server.

Frequently Asked Questions