COMMON CHORD PROGRESSIONS, EXPLAINED. a handful of patterns, a thousand songs

Take the major scale of any key and build a chord on each of its seven notes. You get the same pattern every time: three major chords, three minor chords and one diminished chord. Musicians number them by the scale step they start on, in Roman numerals, with capitals for major and small letters for minor: I, ii, iii, IV, V, vi and vii°.

In C major that gives C, Dm, Em, F, G, Am and Bdim. In G major it gives G, Am, Bm, C, D, Em and F♯dim. The letters change with the key; the numbers don’t. That is the whole point. When a guitarist says a song goes “one, five, six, four”, every player in the room knows the chords, whatever key the singer wants.

The Nashville number system writes the same idea with ordinary numbers, 1 to 7, and adds an m for minor: 1, 2m, 3m, 4, 5, 6m. This page uses Roman numerals because they’re the more common way to write progressions down, but the two say the same thing.

Why do so few patterns cover so many songs? Because the I, IV and V chords between them hold every note of the scale, and the vi is the I’s relative minor, sharing two of its three notes. Those four chords can harmonise almost any melody in the key. The progressions below are the orders that sound best, and the ones your ear has been hearing since childhood.

I–V–vi–IV. C, G, Am, F in C; G, D, Em, C in G. The best-known progression in pop. It lifts, dips into the minor and settles back, and it loops forever without sounding finished, which is why so many choruses run on it.

vi–IV–I–V. Am, F, C, G in C. The same four chords started from the minor one. Starting on vi makes the song sound darker and more yearning, even though nothing else has changed.

I–IV–V. C, F, G in C; G, C, D in G; A, D, E in A. The three-chord trick of folk, country, rock and roll and campfire songs. The V chord pulls hard back to I, so a phrase that ends on V sounds like a question and one that ends on I sounds like the answer.

I–vi–IV–V. C, Am, F, G in C. The doo-wop and fifties ballad progression. Swap the IV for a ii (C, Am, Dm, G) and you have the same feel with a slightly smoother bass.

ii–V–I. Dm, G, C in C, usually played as Dm7, G7, Cmaj7. The backbone of jazz standards, and a common way to arrive anywhere: put the ii and V of a chord in front of it and the ear hears that chord as a destination.

The 12-bar blues. Four bars of I, two of IV, two of I, then V, IV, I and a final bar of V (or I) to turn round. In A: A A A A, D D A A, E D A E. Countless blues and rock songs use this frame, often with every chord played as a seventh.

Minor keys have their own numbering, counted from the minor home chord: i, ii°, III, iv, v, VI and VII. In A minor that is Am, Bdim, C, Dm, Em, F and G, the same chords as C major with a different home. The v is very often played major (E instead of Em in A minor) to pull harder back to the i.

i–VI–III–VII. Am, F, C, G in A minor. The same chords as vi–IV–I–V in C, heard with Am as home. It’s all over rock and film music.

i–VII–VI–V. Am, G, F, E. Often called the Andalusian cadence, a bass line stepping down to a major V that leans back to the start. You hear it in flamenco and in plenty of rock songs.

I–♭VII–IV. D, C, G in D. The ♭VII is borrowed: C isn’t in D major, but it sounds right in a riff-based rock song. Borrowed chords like this, the ♭VII, the ♭VI and the minor iv, are how songs add colour without changing key.

Once you know a few progressions, you start hearing them everywhere, and working a song out gets much faster: you recognise the pattern and fill in the chords from the key. Here is how to practise that.

In the Chord Lens Studio you can check yourself. Open a song, turn on Nashville in the chord sheet, and every chord on the chart becomes its number in the song’s key, with “1 = B” (or whatever the key is) beside the key. The demo song in the screenshot runs 1, 4, 6m, 5 in its chorus: I, IV, vi, V in Roman numerals.

Because a progression is just numbers, you can play it in any key. A song that goes I–V–vi–IV in E (E, B, C♯m, A) has awkward shapes for a beginner; the same song in G (G, D, Em, C) is all open chords. Moving a song like that is called transposing, and our guide on how to transpose chords walks through it. Change Song Key does it for the recording and the chart together.

Writing your own songs, the same patterns are a starting point, not a cage. Take I–V–vi–IV and change one chord: swap the V for a iii, end on the IV instead of returning home, or borrow a ♭VII. Small changes to a familiar shape are how a lot of memorable songs are written.

To find the progression of a song you have as a file, drop it into the AI Chord Finder and read the chart, with Nashville on if you want the numbers. For a song on YouTube, paste the link into YouTube to Chords. Then check it by ear: the pattern you hear should match the numbers you read.