Runs entirely on your device
Your audio is decoded and re-timed with the Web Audio API in the browser. Nothing is uploaded, so voice memos, unreleased beats and confidential recordings never leave your machine.
AUDIO TOOLS · RUNS LOCALLY
Audio speed changer
Speed up or slow down any song in your browser, keep the pitch or let it move with the speed, and make a nightcore or slowed + reverb version in one press.
FREE · NO ACCOUNT · 100% LOCAL PROCESSING · EXPORT WAV
WHY THIS ONE
Accurate tempo control without server upload or compression loss
Most online audio changers upload your files to distant servers, queue processing, and re-compress your music. PrismPoster does it instantly in Web Audio.
Pitch-Lock Preservation
Speed up dialogue or slow down tricky musical solos without sounding like a chipmunk or demon.
0.25x to 4.0x, in fine steps
Slow a solo down to learn it note by note or speed a lecture up to save time — the whole range from 0.25x to 4.0x is on one slider, with a one-tap reset to 1.0x.
PAST THE PAGE
Need full stems or original compositions?
Music Studio writes and sings songs in 35 languages and splits finished tracks into stems.
- Split vocals and instrumental stems with AI vocal remover.
- Generate complete genre tracks with customizable BPM.
- In many countries a new account gets 200 free starter credits, no card. Unused starter credits expire 24 hours after they are granted.
This browser tool is free and requires no account.
Explore Music StudioQUESTIONS
Audio speed & tempo, answered
Is the audio speed changer free?
Yes. It needs no account and processes the file in your browser, so there is nothing to meter. Generating full songs or stems is what PrismPoster Music Studio does, on credits.
Can I change speed without changing pitch?
Yes. Leave “Preserve pitch” on and the tool time-stretches instead of resampling, so a slowed-down solo stays in key. Turn it off for the classic tape-style effect where pitch follows speed.
How do I make a nightcore version of a song?
Load the song and press Nightcore: it plays at 1.25x with the pitch rising with the speed, the brighter sound the style is known for. Export it as a WAV when it sounds right.
How do I make a slowed + reverb version?
Press Slowed + reverb: the song plays at 0.8x, the pitch drops with it and a long room reverb is added. Preview it, adjust the speed if you like, then export the WAV.
Which audio formats can I load?
Anything your browser can decode: MP3, WAV, AAC/M4A, OGG and FLAC on current Chrome, Safari, Firefox and Edge. Very long files are limited by device memory, since the whole track is held decoded.
Does it upload my audio anywhere?
No. Decoding, time-stretching and the WAV export all run with the Web Audio API on your device. Closing the tab discards everything.
What format is the export?
A 16-bit PCM WAV at the source sample rate — lossless, so nothing is re-compressed. Convert it to MP3 afterwards if you need a smaller file.
Make the track, not just the edit
Describe a song and the Music Studio writes and sings it.
200 free starter credits in many countries · No card · Unused starter credits expire after 24 hours
No subscription: credit packs from €3.99, paid once. The credits you buy never expire.
Start creating freeReady to produce full audio?Generate, isolate, and arrange.
Create broadcast-ready tracks, isolate stems, and generate synced visuals in one workspace.