pitcher

Free and open source

Change the key of any song. Keep the tempo.

pitcher moves music up or down by any interval, from a full octave to a single cent, while the rhythm stays exactly where it was. Find the key with the built-in tuner, loop and slow down the hard parts, and save the version you need as a file you can share.

Download for Android Desktop and web
  • Works offline
  • No account
  • No ads or tracking
  • GPL-3.0
The pitcher studio on Android: the pitch in cents with the interval above it, a waveform with loops and bookmarks, playback controls, and a shelf of kept pitches

Made for people who make music

The same song, in the key that works for you.

Singers

Bring a song into your range. Try a few keys by ear, keep the ones that fit, and save a backing track in the key you will perform.

Players

Play along with a recording that was tuned differently or capoed, or move a tune to a key that suits your instrument. Shifts can be as small as one cent.

Learners and teachers

Loop a passage, slow it down without changing the pitch, and mark the places you want to come back to. Save a practice file at the slower speed.

How it works

Three steps, all on your phone.

  1. Open a song

    Import an audio or video file, or share one into pitcher from any other app. Only the audio is kept.

  2. Find your pitch

    Slide up or down on the screen and hear the change as the song plays. Or let the tuner name the note you hear, choose the note you want, and apply the interval in one tap.

  3. Keep it and save it

    Keep the pitches you like. Each one is prepared in the background, so saving it as a file or sharing it is quick.

Features

Everything in the Android app, version 2.6.

  • Shift by any amount from one octave down to one octave up, in cents or semitones
  • A full-screen pitch control: slow movements are fine, fast ones are coarse, and snap lands on semitones
  • The interval is spelled out as you go, for example "up a minor third"
  • A tuner that detects the note at the playhead or at a bookmark, keeping the exact cents
  • Loops for the passages you practice, repeated one at a time or in sequence
  • Bookmarks with names, shown right on the waveform
  • Play speed from half to double, without changing the pitch
  • A shelf of kept pitches, one tap to switch between them
  • Save or share as WAV, MP3, M4A, or Opus, the whole song or just your loops
  • Save at your practice speed when you want a slower file
  • Files sound exactly like the preview, because both use the same engine
  • Playback continues in the background and pauses for calls
A new pitch waiting on the shelf with a dashed outline, ready to be kept with one tap

A closer look

A short guided tour points out every control the first time you open a song. You can replay it from Settings.

The studio with a song transposed down a tritone
The studio: pitch, waveform, loops, and kept pitches
A dashed pill for a pitch that is not kept yet
Tap the dashed pill to keep the pitch you are on
The guided tour highlighting the pitch control
The guided tour, one control at a time
The library of imported songs
Your library of songs

Your music stays on your phone

The Android app has no network permission at all. Nothing is uploaded, nothing is tracked, and there is no account to create. Files you save go to your Music folder, or to any folder you choose.

On your computer

pitcher also runs on Linux as a command line tool and a local web app, using the Rubber Band library for studio-quality shifting with formant preservation.

Command line

Shift files, detect notes, and keep a shelf of versions from the terminal. Good for batches and scripts.

Web app

A browser interface with a waveform, a pitch fader, a tuner, and a shelf of versions. It runs on your own machine, so your audio never leaves it.

See the web app → 
# Debian or Ubuntu
sudo apt install rubberband-cli librubberband-dev aubio-tools libaubio-dev ffmpeg yt-dlp
cargo build --release

./target/release/pitcher pitch in.wav out.wav --cents -100 --formant
./target/release/pitcher detect in.wav --at 12.3
./scripts/pitcher-web.sh    # opens the web app on a free local port

Install on Android

  1. Download

    Get pitcher-android-v2.6.4.apk from the latest release.

  2. Install

    Open the file on your phone. Android asks once to allow installs from your browser or file manager.

  3. Update

    New versions install over the old one and keep your songs and pitches. Requires Android 10 or newer.

Questions

Does changing the pitch change the speed?

No. The tempo stays exactly the same. Speed is a separate control, and it never changes the pitch either.

How small a change can I make?

One cent, a hundredth of a semitone. That is enough to match a recording that is slightly out of standard tuning.

Will the saved file sound like what I heard?

Yes. Playback and saved files use the same shifting engine, so the file matches the preview.

Which formats can I save?

WAV, MP3, M4A, and Opus. You can save the whole song or only your loops, joined into one file, at normal speed or at your practice speed.

Does it need the internet?

No. The Android app works completely offline and cannot reach the network.

Is it really free?

Yes. pitcher is free and open source software under the GPL-3.0 license. There are no ads, purchases, or subscriptions.

About

pitcher is free software under the GPL-3.0 license. Everything it ships is free and open source. On Android it shifts with the Sonic engine from Android's Media3 library and uses Android's own open-source codecs, never a phone maker's closed-source codec unless the phone has nothing else. On the desktop it uses the Rubber Band library. Use it with audio you have the right to process.