Free Online Tempo Changer

Speed a track up or slow it down, pitch preserved.

Free to use on Mac, Windows, and mobileNo installation requiredTLS encryption keeps your files safe

What is this tool

AudioToolKit changes the tempo of audio online for free, in your browser. Slow a track to 0.5x or speed it up to 2x with a granular time-stretch that keeps the pitch exactly where it was — no chipmunk or sludge effect. Use it to study music, fast-cut video, or create half-speed audio, then export as MP3 or WAV without uploading the file.

Drag and drop your files here

MP3, WAV, M4A, AAC, OGG, FLAC, AIFF, AIF, OPUS, WMA, AMR — up to 25 MB per file

Rate

1 = original, <1 slower, >1 faster.

Output format

Output

Tempo-changed MP3 or WAV

Accepted formats

.mp3, .wav, .m4a, .aac, .ogg, .flac, .aiff, .aif, .opus, .wma, .amr

Why use this free tool

Slow a track down to study it, speed it up for a fast cut, or create the half-speed effect used in slowed audio. The time-stretch keeps the pitch exactly where it was.

How does the free tempo changer work?

1
Upload the track.
2
Set the rate: 0.8 slows it to 80%, 1.25 speeds it up.
3
Press Process and download.

Frequently asked questions

Does the pitch change?

No. The granular time-stretch changes duration only, so the key stays the same.

What is the range?

0.5x (half speed) to 2x (double speed).

Is there a slowed + reverb preset?

Yes — the Slowed & Reverb preset combines 0.8x tempo with a medium reverb.