Side by side

ChordProgressions.org vs OtoTheory

Both stand on chord finder software. Which one you can start free with, which one lets you read the code, and what each costs once you pay.

ChordProgressions.org

Free plan Web

ChordProgressions.org pairs progression creation and theory analysis with practice tools and a wide range of exports. Its studio playback and editing depend on JavaScript, while projects and imported files stay in the browser.

Visit ChordProgressions.org

OtoTheory

Free plan iPhoneWeb

OtoTheory brings progression building, song analysis, grooves, and theory tools together for players and composers. Check its iOS-only Pro restriction and free-plan export limits against your workflow.

Visit OtoTheory

The facts

	ChordProgressions.org	OtoTheory
Free plan	Yes	Yes
Open source	Not published	Not published
Runs on	Web	iPhone, Web
Lowest paid plan	Free or on request	Lifetime: $99.99, paid once
Plans published	1	3
Maker	Not published	Not published
Website	chordprogressions.org	ototheory.com
On chord finder software	#13 of 27	#17 of 27

ChordProgressions.org: what it does well

Free browser-based studio for guitar and piano.
Offers a generator, analyzer, finder, and transposer.
Imports MIDI, MusicXML, project files, and chord sheets.
Projects autosave locally and imported files are not uploaded.
Exports include MIDI, PDF, MusicXML, and more.

What to know first

JavaScript is required for studio playback and editing.
Audio chord timelines are estimates, though editable.
Studio playback and editing require a browser.

OtoTheory: what it does well

Analyzes chords, key, and song sections on iOS
Includes 19 groove patterns and 50+ presets
Exports MIDI with BPM and section markers on Pro
Offers chord playback and reverse chord lookup

What to know first

Free plan limits users to three local sketch saves
Free plan has no MIDI or audio export
Pro is iOS-only; web features are limited

Alternatives to ChordProgressions.org Alternatives to OtoTheory The whole list