Speed Changer Online
Free Audio Speed Adjuster
Speed up or slow down your audio files while preserving pitch. Perfect for podcasts, audiobooks, lectures, and music. Professional time-stretching algorithms for superior quality.
Upload Audio Files
Drag and drop your audio files here, or click to browse
Supports: Supports MP3, WAV, FLAC, AAC, M4A, OGG, and more
How to Change Audio Speed
Simple steps to adjust audio speed while preserving pitch
Upload Audio File
Drag and drop your audio file or click to browse. Supports MP3, WAV, FLAC, AAC, M4A, OGG, and more formats.
Choose Speed Settings
Select from 7 optimized presets or use custom speed control. Toggle pitch preservation and quality mode for best results.
Change Speed
Click 'Change Speed' to process your audio. Apply speed adjustments with optional pitch preservation.
Download Result
Download your speed-adjusted audio file. All processing happens locally - no uploads required.
Key Features
Everything you need to adjust audio speed perfectly
Pitch Preservation
Maintain the original pitch when changing speed. No chipmunk voices or slow-motion effects unless you want them. Perfect for natural listening.
Wide Speed Range
Adjust speed from 0.25x (quarter speed) to 4.0x (quadruple speed). Perfect for everything from detailed study to quick review.
Quality Algorithms
Choose between fast processing (atempo) or high-quality mode (rubberband) for superior results, especially at extreme speeds.
7 Speed Presets
Quick presets: 0.5x (half), 0.75x (slow), 1.0x (normal), 1.25x (faster), 1.5x (fast), 2.0x (double). Perfect for common use cases.
Privacy First
All speed adjustment happens in your browser using FFmpeg. Your audio files never leave your device. Complete privacy guaranteed.
Batch Processing
Process multiple audio files at once. Perfect for adjusting entire audiobook chapters or podcast series.
Common Use Cases
Podcast Consumption
Speed up podcasts to 1.25x or 1.5x to save time while maintaining clear, natural speech. Perfect for busy schedules and content consumption optimization.
Language Learning
Slow down native speaker audio to 0.5x or 0.75x for easier comprehension. Catch every word and improve pronunciation.
Video Tutorials
Adjust tutorial speed based on complexity. Slow down for detailed steps, speed up for familiar content.
Music Practice
Slow down music to 0.5x to learn difficult passages. Practice at reduced speed before increasing tempo gradually.
Algorithm Comparison
Standard (atempo)
- • Fast processing
- • Good quality
- • Best for 0.5x-2.0x
- • Preserves pitch
High Quality (rubberband)
- • Slower processing
- • Superior quality
- • Best for extreme speeds
- • Preserves pitch
Resampling
- • Fastest processing
- • Changes pitch
- • Natural effect
- • Creative use
Related Audio Tools
More tools to help you work with audio files
Frequently Asked Questions
What's the difference between speed changer and tempo changer?
Speed changer can change both speed and pitch together, or preserve pitch while changing speed. Tempo changer uses professional Rubberband algorithm optimized for music. Use speed changer for podcasts and voice content, tempo changer for music.
Should I preserve pitch when changing speed?
Yes, for podcasts, audiobooks, and lectures - this keeps voices natural. No, for creative effects like chipmunk voices or slow-motion effects. It depends on your use case.
What's the best speed for podcast consumption?
Most people prefer 1.25x to 1.5x for podcasts. Start with 1.25x and increase if comfortable. Higher speeds (1.75x-2.0x) work well for familiar content or fast speakers.
Which algorithm should I use?
Use standard (atempo) for speeds between 0.5x-2.0x - it's fast and good quality. Use high quality (rubberband) for extreme speeds or when quality is critical. Use resampling only for creative pitch-changing effects.
What file formats are supported?
We support all common audio formats: MP3, WAV, FLAC, AAC, M4A, OGG, WMA, AIFF, and more. You can also extract and adjust speed of audio from video files (MP4, AVI, MOV, MKV).
Are my files safe and private?
Absolutely! All speed adjustment happens locally in your browser using FFmpeg. Your audio files never leave your device or get uploaded to any server. Complete privacy guaranteed.