AudioAdjustable qualityRuns in your browser

Change Audio Speed

Play a recording faster or slower, from 0.25× to 4×, without the chipmunk effect — voices keep a natural pitch. Some detail is discarded to fit the target format; how much depends on the format and your settings.

Not uploaded to any serverConverted on this deviceGone when you close the tabHow this works

Drop your files here

MP3, WAV, FLAC, AAC and 5 more formats · up to 300 MB each

or paste files from your clipboard

Ready when you are

Play a recording faster or slower, from 0.25× to 4×, without the chipmunk effect — voices keep a natural pitch. Everything happens in this tab; nothing is sent anywhere.

⌘K to search converters

How to use it

1
Add your files
Change Audio Speed works with MP3, WAV, FLAC, AAC, M4A, OGG, Opus, AIFF and WMA. Drop them in, browse for them, or paste from your clipboard.
2
Choose your options
Tune bitrate, sample rate and channels — or leave the defaults, which are sensible.
3
Run it and download
Press the button and save the result. Everything happens on your device, and nothing is uploaded.

Privacy, in plain words

Is it safe? Your audio file is not uploaded anywhere

What “uploaded” normally means. On most online converters, pressing the button copies your file across the internet onto a computer owned by that website. That copy is what the word “upload” means, and it is the part nobody explains.

What happens instead. This site does not do it. There is no server here that receives files, so your audio file is read, converted and handed back by the browser you are using right now. It never travels — so there is no copy to store, read, leak or hand over.

Check it yourself in ten seconds

Turn off your Wi-Fi after this page has loaded, then convert a file anyway. It still works, because everything needed is already on your device.

The longer explanation of how this works, and the full detail of what is and is not stored on the privacy page.

Why this matters more than it sounds

An audio file is a conversation. Transcribed by machine — which is cheap now — it becomes searchable text about whoever was speaking. It matters more than it sounds, because of what audio files usually are:

Voice notes and dictation

thinking out loud, never meant for an audience

Therapy and consultation recordings

clinical material with strict handling rules

Meeting audio

internal discussion, named people, unannounced decisions

Unreleased music

work whose commercial value depends on control of the master

A file that is never sent cannot be kept, leaked, subpoenaed or used to train anything. That is a property of how this works, not a promise about how carefully it is run.

Faster without the chipmunk voice

Playing a tape faster raises the pitch, because the same waves arrive more often. This tool does it differently: it stretches or squeezes the recording in time while keeping each sound's pitch where it was, so a lecture at 1.5× sounds like a quick speaker rather than a cartoon.

The technique works by cutting the sound into short overlapping slices and laying them closer together or further apart. Speech and most music survive it well up to about double speed. At the extremes — a quarter speed or four times — you will start to hear a slight echo or flutter, which is the seams between slices becoming audible.

Good for: Lectures, podcasts, interviews and voice notes you want to get through quicker, or a passage of music slowed down to learn.
The length changes: A one-hour recording at 1.5× becomes forty minutes. The result shows the new duration once it is done.

About these formats

Accepts

MPEG-1 Audio Layer III

The universal lossy audio format.

Extensions: .mp3
MIME type: audio/mpeg
Best for: Music players · Podcasts · Maximum compatibility
Compatibility: Plays absolutely everywhere.

Accepts

Waveform Audio

Uncompressed PCM audio. Perfect quality, big files.

Extensions: .wav, .wave
MIME type: audio/wav
Best for: Editing and mastering · Sound design · Archival
Compatibility: Universal.

Good to know

Change Audio Speed — questions

How does Change Audio Speed work?

Play a recording faster or slower, from 0.25× to 4×, without the chipmunk effect — voices keep a natural pitch. Add your files above, adjust anything you want to change, and press the button. The result downloads straight to your device.

Is Change Audio Speed safe — are my files uploaded to a server?

No, nothing is uploaded. On most online tools, pressing the button copies your file across the internet onto a computer owned by that website, where it is processed and then sent back. That copy is what "upload" means. This tool does not do it: your file is read and processed by the browser you are using right now, stays on this device the whole time, and is discarded when you close the tab. Turn off your Wi-Fi after the page loads and it still works, which is the quickest way to confirm it.

Can I use this on confidential or personal documents?

Yes — that is the case it was built for. Because the file never leaves your device, a confidential document is no more exposed than it is sitting in your own folder: there is no transfer, no copy on anybody else's hardware, no retention period and no staff with access. Nothing about the file is logged either — not its name, not its size, not its contents.