At a glance
- Accepts
- MP3, WAV, M4A, AAC, OGG, Opus, FLAC, and the audio track of a video
- Outputs
- The changed song as a 44.1 kHz stereo MP3 (192 kbps) or WAV, plus the detected key and BPM before and after
- Where it runs
- Entirely in your browser, on your device
- What leaves your device
- Nothing - the file never leaves your device
- Limits
- Key -12 to +12 semitones and speed 50% to 150%; changes beyond a few semitones or outside about 80-120% speed start to sound processed, voices most of all; the whole song is held in memory, so very long files can be too much for a phone
- Account
- Not required - there is no sign-up
- Price
- Free, with no watermark and no usage cap
- Made by
- Visrut
- Last updated
- 23 October 2026
Move a song up or down in key without changing its speed, or slow it down without changing its pitch. You hear every change straight away while the song plays, and download the result as MP3 or WAV. It is made for singers who need a song in their key, musicians practising a part at a slower tempo, and dancers matching a track to a routine. Everything runs in your browser, so the song is never uploaded.
How to use it
- Drop in a song, or a video to use its soundtrack.
- Press play, then move the key in semitones or the speed in percent while it plays. Use Hear the original to compare.
- Pick MP3 or WAV and download the new version.
How it works
Changing the playback rate of a recording changes its pitch and speed together, like a record played too fast. To change one without the other, the tool takes the song apart into short overlapping slices of frequencies, moves those frequencies up or down (or spaces the slices further apart or closer together), and puts the sound back together. It uses Signalsmith Stretch, an open-source library designed for whole songs with many instruments at once, where simpler methods make chords and cymbals warble. The key and tempo shown next to the sliders come from the same analysis as the BPM & Key Finder.
Making a karaoke track in your key?
Take the vocals out first with Remove Vocals, then bring the instrumental here and move it to a key that suits your voice. Both run in your browser.
Frequently asked questions
Does changing the key change the speed, or the other way round?
No. The two are independent: you can move a song up two semitones and it plays at exactly the same tempo, or slow it to 80% and it stays in the same key. That is the difference from speeding up a record or changing the playback rate, where a faster song is also higher.
How much can I change before it sounds strange?
A few semitones up or down, and speeds between about 80% and 120%, usually sound natural. Bigger changes still work, but voices start to sound unnatural (a singer moved up 7 semitones sounds small and bright, moved down sounds big and dark) and drums lose some of their snap at very slow speeds. That is true of every pitch shifter, not just this one.
How do I make a karaoke track in my key?
First take the vocals out with Remove Vocals, which runs in your browser too and gives you the instrumental. Then drop that instrumental here, move the key until it sits comfortably for your voice, and download it. Singing along with the preview while you move the key is the quickest way to find the right one.
Can I slow a song down to practise it?
Yes. Set the speed to 70% or 80% to learn a solo or a dance routine at a slower tempo, without the pitch dropping. If the song's tempo is detected, you can also type a target BPM and the speed is worked out for you.
Is my song uploaded?
No. The song is decoded, played and processed inside your browser tab, and the file you download is made there too. Nothing is sent to a server, and the page keeps working if you go offline after it loads.
What does a semitone mean?
A semitone is the smallest step in Western music, one key to the next on a piano, including the black keys. Twelve semitones make an octave. Moving a song in G major up 2 semitones puts it in A major. If the key of the song is detected, the tool shows the new key as you move the slider.