Freedom to Play

Ultimate Music Theory Reference
for Guitar, Bass & Ukulele

  1. Always know which chords to play together
  2. Improve soloing and improvisation skills
  3. Create your own signature sound

Bring Your Own Strings

Guitar, Bass & Ukulele

Not just for guitarists — StringTheoryPRO works for bass guitar and ukulele too. Every chord and scale in every key and mode can be viewed for guitar, bass and ukulele.

A roadmap that shows you what is available to play on your instrument.

With palettes of chords that sound good together the musician is free to explore and play creatively.

Basics

Immediately increase your creative potential

Ideas

Play together with friends on other instruments

Level Up

Transfer your skills on guitar to ukulele or bass guitar

Chords · Chords · Chords

Chords that are Meant for Each Other

The average chord dictionary is a large collection of random chords with zero context. Useful for looking up a specific chord — but what if you're not sure what chord your looking for?

When you know what works, you can focus on making music!

StringTheoryPRO helps you find just the right chords to play together. Chords are shown in context with a musical key, so you can have fun experimenting with different combinations with confidence.

Basics

See which chords play well together

Ideas

Discover alternate chords to make your music more interesting

Level Up

Identify key intervals in your chords

Show notes as finger
Show notes as interval
Show notes as name
Show notes as finger
Show notes as interval
Show notes as name
Show notes as finger
Show notes as interval
Show notes as name
These chords sound good together

A Creative Boost

Chord Progressions

StringTheoryPRO includes a collection of the most useful chord progressions across multiple genres. Chord progression can be instantly transposed to any key or mode. Use them for inspiration, experiment just for fun or incorporate one into your next song.

Basics

Learn a variety of popular chord progressions

Ideas

Find inspiration for your next song

Level Up

Change chord progressions into other keys and modes

“Reflections”
Folk

Creates an emotional, reflective feel common in acoustic ballads and indie-folk.

1
vi
A min
IV
F Maj
I
C Maj
V
G Maj
2
vi
A min
IV
F Maj
V
G Maj
V7
G7

Key of C Ionian

Master the Fretboard

CAGED: Chords in Every Position

Every chord can be played in 5 different positions using the 5 chord forms. It doesn't stop with chords - knowing how to locate the CAGED shapes helps with soloing too.

Play chords where you want — in any position on the fretboard.

Click any of the C·A·G·E·D chord form buttons to switch between the 5 positions of a chord.

Basics

Learn new options for playing chords you already know

Ideas

Pick a chord and try playing it in all five CAGED positions

Level Up

Unlock better soloing and improvisation

Show notes as finger
Show notes as interval
Show notes as name

Finding Every Note

Scales in Key

Learning scales is a core component to mastering your instrument. Scales are for more than just practicing - they are a way of learning to find the notes you need to make the sounds you want.

Many of the fastest and cleanest players built their technique largely through dedicated scale practice.

A key concept is pairing the correct scale with the your chord progression. StringTheoryPRO makes this a breeze, by always grouping the scales that match your selected key and mode.

Basics

Which scales fit with different chords

Ideas

Add a melody to your chord progression

Level Up

Learning scales to improve your solo playing

  1. B

  2. C

  3. D

  1. G

  2. A

  1. D

  2. E

  3. F

  1. A

  2. B

  3. C

  1. E

  2. F

  3. G

  1. B

  2. C

  3. D

Feeling Moody?

A Mode for Every Mood

The struggle is over... It's easier than ever to play with modes. StringTheoryPRO allows you to instantly switch between modes. Chords, scales, progressions are automatically transposed into the mode of your choosing.

Create your own signature sound

Most of us are familiar with the Major and Minor modes - there are actually seven different modes, each with their own unique sound qualities. Experiment with using modes to affect the character of your music.

Basics

Switching modes effects the mood of your music

Ideas

Choose a chord you're familiar with and try switching modes

Level Up

Use modes to impart a sense of emotion to your music

  1. Lydian Dreamy, Light, Uplifting
  2. Ionian Cheerful, Bright, Optimistic
  3. Mixolydian Playful, Warm, Friendly
  4. Dorian Soulful, Mellow, Expressive
  5. Aeolian Gloomy, Emotional, Introspective
  6. Phrygian Dark, Exotic, Mysterious
  7. Locrian Tense, Dark, Unsettling

Find the Sweet Spot

Chord Tones

A simple concept with powerful uses. Playing chord tones over the chords in a progression is an instant level up for solos.

Your solos suddenly sound "in the song" instead of just "over it"

StringTheoryPRO shows you where to find the chord tones that match any chord, everywhere on the fretboard.

Basics

Chord tones are the notes that make up a chord

Ideas

Try intentionally targeting chord tones when soloing over chord changes

Level Up

Always find the right note that fits the feel you're aiming for

  1. 1

  1. 3

  2. 5

  1. 1

  1. 3

  1. 5

  1. 1

Mild, Medium or Spicy?

Chords that Add Flavor

Searching for the perfect chord to complete your progression? Using spice chords can add color and character to your music.

Give your music an unique, professional sound.

Spice chords are chords that use notes from outside the current key. Also called borrowed chords or non-diatonic chords. Adding spice chords is a fast way to sound more sophisticated without needing complex technique.

Basics

Sometimes playing the "wrong" chord sounds great

Ideas

Try experimenting with the spice chords in your songs key

Level Up

Easily identify which spice chords to try with any chord progression

I
Show notes as finger
Show notes as interval
Show notes as name
iii
Show notes as finger
Show notes as interval
Show notes as name
vi
Show notes as finger
Show notes as interval
Show notes as name
iv
Spice! This chord adds flavor to the progression.
Show notes as finger
Show notes as interval
Show notes as name
The F minor chord adds spice to this chord progression

Frequently Asked Questions

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.
Yes! You can start using StringTheoryPRO for free. Access to certain features require upgrading to a PRO subscription.
StringTheoryPRO is already free to try. No credit card is required to sign up for a free account.
Yes! StringTheoryPRO works with guitar, bass guitar, and ukulele.

Yes! StringTheoryPRO can be opened in your browser and installed as a "Progressive Web App" (PWA).

The user interface adapts to the size of your device's screen. We suggest using a tablet for the best experience on mobile devices.

Installing on Android Devices
  1. Open https://stringtheory.pro on your device with the Google Chrome browser
  2. Tap the menu button (3 dots) at the top of the screen
  3. Tap Add to Home Screen
  4. Tap Install
Installing on iOS Devices
  1. Open https://stringtheory.pro on your device with the Safari browser
  2. Tap the share button (the square with an upward arrow) at the bottom of the screen
  3. Scroll down in the share menu and tap Add to Home Screen
  4. Tap Add in the top right