Chord Progression Builder
Choose a key and a progression, or build your own from the chords that belong to the key. See every shape, then loop it as a backing track to practise over.
Soloing over the loop? Every chord here comes from the G major scale — or keep it simple with the minor pentatonic of the relative minor.
How to Use the Builder
- Pick a key and major or minor. Switching mode loads a starter progression for that mode.
- Choose a preset, or press Clear and build your own by clicking chords in the palette. The palette only offers chords that belong to the key, plus the common 7th-chord and major-V variations. Click the × on a chord to remove it.
- Press Loop it. The current chord lights up as it plays. Choose a feel: one strum per bar for a pad to solo over, quarter notes or the folk strum to play along with, or a picked arpeggio for something gentler.
- Set the tempo, and change chords every one or two bars.
The Presets
Here is each preset in a guitar-friendly key, G major or E minor, with what makes it work.
| Progression | In G / E minor | Character |
|---|---|---|
| I – V – vi – IV | G D Em C | The four chords behind a huge share of modern pop. Start it on the vi and it becomes the "sad" version. |
| I – vi – IV – V | G Em C D | The doo-wop progression. Same four chords as the pop progression, in a different order. |
| I – IV – V – I | G C D G | The three primary chords. Folk, country, early rock and roll, and most campfire songs. |
| vi – IV – I – V | Em C G D | The pop progression rotated to start on the minor chord, which makes the whole loop feel darker. |
| ii7 – V7 – Imaj7 | Am7 D7 Gmaj7 Gmaj7 | The cadence jazz is built on. The V7 pulls hard to the I; learn to hear that pull. |
| 12-bar blues | G7 G7 G7 G7 C7 C7 G7 G7 D7 C7 G7 D7 | Twelve bars, three dominant 7th chords. The last bar is the turnaround back to the top. Solo over it with the minor pentatonic or blues scale. |
| i – VI – III – VII | Em C G D | A minor-key loop heard across rock and film music — the relative of the major pop progression. |
| i – iv – V – i | Em Am B Em | Minor-key three-chord song, with the V made major (from harmonic minor) so it resolves strongly. |
| i – VII – VI – V | Em D C B | The Andalusian cadence: a stepwise walk down to a major V. Flamenco, surf rock, and countless minor-key ballads. |
| i – VII – VI – VII | Em D C D | A rocking back-and-forth that never fully resolves — good for long jams and soloing practice. |
Why Numbers Beat Chord Names
Musicians describe progressions by number because the numbers are what you actually hear. A I–IV–V sounds the same in any key: the same lift to the IV, the same pull from the V back home. Learn a progression by its numbers and you know it in all twelve keys at once.
On the guitar the numbers also become shapes. With barre chords, the I, IV and V of any key are close together. The IV is on the next string at the same fret, the V two frets higher. Learn that box once and you can play a blues or a three-chord song anywhere on the neck. The circle of fifths shows the same relationships as a diagram.
Writing Your Own
The diatonic chords, the seven in the palette, are guaranteed to fit together, so any combination will sound reasonable. Some combinations sound better because of how they move:
- End on V to make the loop pull back to the top. A progression ending on the I sounds finished; ending on the V makes the repeat feel inevitable.
- Use the vi for colour. It shares two notes with the I, so it makes the progression darker without leaving the key.
- ii and IV are interchangeable before a V. They share two notes, and ii–V is a little smoother and jazzier.
- Avoid vii° on its own. It is unstable and wants to go to I. Use it as a passing chord, or use the V7, which contains it.
- Try 7th chords. Swap the V for a V7 and the pull home gets stronger. Swap the I for an Imaj7 and it softens.
Practising Over the Loop
The loop is a backing track you can play with at any tempo, which is the missing piece in most solo practice. Some ways to use it:
- Comping. Play the chords yourself along with the loop, using a pattern from the strumming trainer. Turn the loop down to one strum a bar so it is just a guide.
- Soloing. Use the link under the builder to open the key's scale on the scale explorer. Start with the pentatonic, then aim for the chord tones: land on a G note when the G chord plays, a C when the C plays.
- Ear training. Loop a progression without looking at the names and try to call out the numerals. Then check. This is the musical version of the ear trainer's chord rounds.
Every chord in the builder links to its shapes in the chord library. If a shape is hard in one key, try the progression in another. With the numbers fixed, nothing else about it changes.
Frequently Asked Questions
What do the Roman numerals mean?
Each numeral is the chord's position in the key: I is built on the first note of the scale, IV on the fourth, and so on. Uppercase means major, lowercase minor, and ° diminished. Numerals let you describe a progression without naming a key, so I–V–vi–IV is the same progression whether it is G–D–Em–C or C–G–Am–F.
How do I change the key of a progression?
Click a different root note. The numerals stay the same and every chord moves with them, the same thing a capo or transposition does. To move a whole chord sheet, including lyrics, use the chord transposer.
Can I use this as a backing track?
Yes, that is what the loop is for. Press Loop it, set the tempo and feel, and improvise over it with the scale of the key. The link under the builder opens the matching scale on the fretboard. The loop repeats until you stop it.
Why is the V chord major in a minor key?
In the natural minor scale, the fifth chord is minor, and it sounds weak when it leads back home. Most minor-key music raises one note to make the V major, which gives a strong pull back to the i. The palette offers both, and the minor presets use the major V where songs usually do.
Can I share or save a progression?
The address bar updates as you build, so copying the URL saves the key, mode and chords. Open the link later, or send it to someone, and the same progression loads.