Music Theory You Can Use

Chord & Scales for Guitar, Bass & Ukulele

In Every Mode & Key

Try it Free Now Pro Subscription

Choose Your Instrument

Start with a Chord

Get in the Mood

Cheerful, Bright, Optimistic

Dorian

Soulful, Mellow, Expressive

Aeolian

Gloomy, Emotional, Introspective

any old strings

Guitar, Bass & Ukulele

Not just for guitarists. StringTheoryPRO works for bass guitar and ukulele too.

More instruments could be added in the future too. Guitaralele anyone?

What to Play?

Chords and Scales in Every Key

Instantly increase your enjoyment and playing skills. StringTheoryPRO helps you find just the right chords, scales and notes to play together. When you know what works, you can focus on making music!

Feeling Moody?

Choose a Mode to Match the Mood

Its easier than ever to play with modes. StringTheoryPRO organizes modes by mood. Experiment with using modes to affect the character of your music.

Caged Match

The Unified Theory

StringTheoryPRO supports the CAGED system to show you how chords and scales connect across the fretboard. But why stop there? We also integrate scales, modes, pentatonics (and soon arpeggios, triads, shell chords). The reality is all these concepts are interrelated. StringTheoryPRO can help you to see the big picture.

Mild, Medium or Spicy?

Chords that Add Character

Searching for the perfect chord to complete your progression? StringTheoryPRO suggests chords that fit your key and mode. These include borrowed chords from parallel keys, modal interchange chords and other non-diatonic options. Use these to add color and character to your music.

FAQ

Any Question?

Here are some of the most common questions we receive.

What is StringTheoryPRO?

StringTheoryPRO is a web based application that helps guitar, bass, and ukulele players to find chords, scales, and modes to play together. It is not a teaching method but rather a tool to help you apply music theory in a practical way.

Is it Free to Use?

StringTheoryPRO is free to use with access to some keys and modes reserved for PRO subscribers. The free tier features include everything available to PRO users, just limited to certain keys and modes.

Do you offer a free trial?

StringTheoryPRO is already free to try. Please feel free to start using it right away. No credit card is required to sign up for a free account.

Does it work with Ukulele?

Yes! StringTheoryPRO works with guitar, bass, and ukulele. More instruments may be added in the future.

Is there a mobile app version?

Currently, there is no mobile app version of StringTheoryPRO. However, the web application is fully responsive and works well on other devices too. You can access it from your mobile browser. We suggest using a tablet for the best experience on mobile devices.

Does this work with the CAGED system?

Yes! StringTheoryPRO supports many different ways of thinking about chords and scales on the fretboard. Every chords in StringTheoryPRO can be shown in all five CAGED positions.