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effect
Change Audio Speed Online
Speed up or slow down audio with natural pitch shift. Free, private, runs in your browser.
How it works
01
Drop your audio file or click to upload. MP3, WAV, and most formats work.
02
Use the slider or presets to set your speed (0.25x to 4x). Pitch shifts naturally with speed.
03
Preview the result and download as WAV.
No file uploadNo signupNo ads100% browser-based
Frequently asked questions
How do I change the speed of an audio file online?
Upload your audio file, use the slider to set your desired speed (0.25x to 4x), and download the result. Slower speeds lower the pitch, faster speeds raise it, just like a turntable.
Can I slow down music to learn a part?
Yes. Musicians commonly slow songs to 0.5x or 0.75x to learn difficult passages. Upload the song, set the speed, and practice along with the slowed version.
How much does the pitch change?
The tool shows the pitch shift in semitones. Doubling the speed (2x) raises pitch by 12 semitones (one octave). Halving it (0.5x) lowers pitch by 12 semitones. Each semitone is one piano key.
Can I speed up a podcast or lecture?
Yes. 1.25x or 1.5x are popular for listening to podcasts and lectures faster. Upload the audio, set the speed, and download.
Does this upload my file to a server?
No. All processing happens locally in your browser. Your audio file never leaves your device.
Can I use this on my phone?
Yes. Works in any modern mobile browser. No app needed.
What format is the output?
Lossless WAV at the original sample rate. WAV preserves full quality.
Is this speed changer free?
Completely free. No account, no limits, no watermarks.
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