I use this when playing guitar, to retune tracks in E to Eb or D so I can play along on instruments in those tunings. It does affect the sound if you change the pitch while keeping the speed, sounds a little "out of phase" on the guitars, I guess you'd say, BUT it's easy to use, pitch-accurate and free. Totally workable!

Perfect for Nint*ndo songs on yt ;)

Excellente extension pour permettre de pitch les musiques sur vos plateformes favorites

Tips for those who dont want to trust the extension: you can use the extension to make the changes (and then uninstall it)... as long as the page DOES NOT REFRESH, the voice changes are retained!

This extension is really satisfactory for audio and pitch speed changes, whether you decide to alter the tone or not while increasing the speed, the only exception is that when you only increase the pitch, it is barely audible and does with the current one instead of editing exactly that. Otherwise, it works well

Странно работает

works almost perfectly but it stops youtubes built in speedup from working

do ts with speed and pitch 1.2 youtube.com/watch?v=WEQhIdgm0aQ

Works with the speed changer, but the pitch changer does not work properly independently. It will play the audio of the website in its normal key as well as playing the audio of the changed pitch. Sounds horrendous.

Un petit problème à signaler, avec les raccourcis clavier + et -, la tonalité change, mais aussi le tempo :-/
Sinon, ça marche plutôt bien

Well, the pitch change is very low quality, rather unusable.

Perfect add on for karaoke. A must have!

Love it! Now I can finally sing karaoke in lower keys!

This addon is pretty much as good as it gets when it comes to Speed/Pitch Changers, on ANY browser. This addon absolutely TRASHES on the largest one on Chrome (transpose.video), with the latter having to thank it after. Obviously nothing even remotely compares on Firefox or anything else. Excellent work easily one of the best addons a web browser can have, and a genuine W for Firefox.


I strongly agree with the other review on this being very worth porting to Chrome though.

I'd really love if the creator could make a version of this extension for Chrome.

worked better than i would have thought, very good

This was exactly what I was looking for, and has served me well for over a year. I can change the speed and pitch independently and easily.

A great Firefox alternative to the Chrome-only https://transpose.video, which does what it says on the box.

The pitch-shifting algorithm does produce slight artifacting at certain pitches, but overall works well enough to be able to sing along.

*However, keep in mind that for it to work well, the (preserved pitch) option has to be turned off.