Chord Progressions: I–IV–V, I–V–vi–IV and the 12-Bar Blues in Every Key

A chord progression is the order in which chords are played. Chords are numbered with Roman numerals from the notes of the scale, so in C major I is C, IV is F and V is G. The most common progressions are I–IV–V–I, I–V–vi–IV and the 12-bar blues: four bars of I, two of IV, two of I, then V, IV, I and I.

Updated 1 November 2026 · By the Classfern Music Department

UKUSWorks in the UK and the US. This version uses UK words and school years (bar, stave, crotchet, KS2, Year 4); the US version uses measure, staff, quarter note and grades. · US version of this page

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Key facts

• Chords are numbered I to VII from the notes of the scale: in C major, I = C, ii = Dm, iii = Em, IV = F, V = G, vi = Am, vii° = B°.
• Upper-case numerals are major chords, lower-case are minor and ° is diminished.
• I, IV and V are the three primary chords: together they hold every note of the major scale.
• The 12-bar blues: I I I I | IV IV I I | V IV I I, often with 7th chords (I7, IV7, V7).
• A progression often ends V–I, the perfect cadence.

What is a chord progression?

A chord progression is a series of chords played one after another, usually repeating. Musicians name the chords with Roman numerals counted from the key note, so the same progression can be played in any key: I–IV–V is C–F–G in C major and G–C–D in G major.

Build a chord on each note of the major scale, using every other note (1–3–5), and you get three major chords (I, IV, V), three minor chords (ii, iii, vi) and one diminished chord (vii°). In a minor key the pattern is i, ii°, III, iv, v, VI and VII, and the v is often made major (V) by raising the 7th note.

Chord progression player

Choose a progression and a key. Each chord lasts one bar of four beats, with a bass note and a light click; the chord playing now is highlighted and named. Minor progressions use the minor key with the same key signature.

Progression I–IV–V–I (the three-chord trick)I–V–vi–IV (the most common pop progression)I–vi–IV–V (the 1950s progression)vi–IV–I–V (the same chords, starting on vi)ii–V–I (jazz)I–V–vi–iii–IV–I–IV–V (Pachelbel’s Canon)12-bar blues12-bar blues, quick changei–iv–v–i (minor)i–VI–III–VII (minor)i–VII–VI–V (the Andalusian cadence, minor)

Key C (major) / A (minor)G (major) / E (minor)D (major) / B (minor)A (major) / F♯ (minor)E (major) / C♯ (minor)B (major) / G♯ (minor)F♯ (major) / D♯ (minor)D♭ (major) / B♭ (minor)A♭ (major) / F (minor)E♭ (major) / C (minor)B♭ (major) / G (minor)F (major) / D (minor) Play twice

1. CI
2. FIV
3. GV
4. CI

I–IV–V–I (the three-chord trick) in C major: C | F | G | C.

Play the progressionSpeed 96 beats a minute

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What is the I–IV–V chord progression?

I–IV–V uses the three primary chords of a key: the chords built on the 1st, 4th and 5th notes of the scale. In C major they are C, F and G; in G major, G, C and D. Thousands of folk, rock, country and blues songs use only these three chords, which is why guitarists call it the three-chord trick.

Easy keys for beginners: G, C, D and A on guitar and ukulele; C, G and F on piano. See the shapes on Classfern’s piano chord chart or the guitar chord chart.

What is the 12-bar blues?

The 12-bar blues is a chord progression 12 bars long, built from I, IV and V: four bars of I, two of IV, two of I, then one each of V, IV, I and I. It is the basis of blues, early rock and roll and much jazz, and is usually played with 7th chords.

Variations: the quick change moves to IV in bar 2; a turnaround puts V in bar 12 to lead back to the start; slow blues often uses 12/8 time. W. C. Handy, who published blues sheet music from 1912, helped fix the 12-bar form so musicians could share it. Choose “12-bar blues” in the player above to hear it in any key.

What are the most common chord progressions?

The most common chord progressions are I–IV–V–I, I–V–vi–IV (heard in a huge number of pop songs since the 1990s), I–vi–IV–V (the 1950s doo-wop progression), ii–V–I (the backbone of jazz) and the 12-bar blues. In minor keys, i–iv–v and the Andalusian cadence i–VII–VI–V are favourites.

• I–V–vi–IV: in C, C–G–Am–F. Start it on vi (Am–F–C–G) for a sadder sound.
• I–V–vi–iii–IV–I–IV–V: the bass of Pachelbel’s Canon in D (Johann Pachelbel, died 1706).
• ii–V–I: in C, Dm7–G7–Cmaj7, usually with 7th chords.
• i–VII–VI–V: in A minor, Am–G–F–E, the Spanish-sounding Andalusian cadence.

How do you write a chord progression?

Pick a key, start on chord I, wander through IV, V and the minor chords ii, iii and vi, then come home with V–I. Songs usually change chord once or twice a bar and repeat a four-chord pattern; strong progressions often move the root down by a fifth, as in vi–ii–V–I.

1. Choose a key that suits your voice or instrument.
2. Begin and end on I so the music feels at home.
3. Use V (or V7) just before the end: V–I is the perfect cadence, IV–I the plagal (“Amen”) cadence, and stopping on V the imperfect cadence.
4. Play it on a loop and sing over it – Classfern’s free backing tracks help.

Chord progressions quiz

Marked by Classfern 5 multiple-choice questions on the Classfern lesson engine. Your answers stay on this device.

Start the quiz

Classroom idea: a 12-bar blues in 20 minutes

A whole-class activity for KS2 and KS3 (Years 4–9) with keyboards, glockenspiels or voices. Set the player above to 12-bar blues in C at about 90 beats a minute.

1. Feel it (3 minutes): play the progression and clap on beats 2 and 4 while you count the bars out loud.
2. Three teams (5 minutes): split the class into C, F and G teams. Each team stands and sings its root note on “doo” when its chord comes round.
3. Swap (4 minutes): rotate the teams, then try the quick change, where F comes in bar 2.
4. Improvise (6 minutes): volunteers play the C blues scale (C E♭ F G♭ G B♭) over the chords, two bars each.
5. Check (2 minutes): Judged by a teacher or parent (rubric) keeps a steady beat; changes chord at the right bar without help; can name I, IV and V in C.

Classfern’s free chord progression player is part of the Classfern Music Department at lessonplanner.info. Chord names are spelled from the key, so F♯ major shows E♯°, not F°.

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