Roman Numeral Chords Explained: Read Any Chord Progression in Any Key
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You open a tutorial, a forum thread or a MIDI pack and the chords aren't written as C, G, Am and F. Instead you see I, V, vi, IV. Or i, VI, III, VII. Or someone in the comments says "it's just a ii-V-I". If that looks like homework, don't worry. Roman numerals are one of the most useful shortcuts in music, and you can learn to read them in about ten minutes.
This guide shows you what the numerals mean, how to turn them into real chords in any key, and how to use them to write and transpose progressions in your DAW. No sheet music needed.
The short answer
A Roman numeral tells you which note of the scale a chord is built on, not which letter it is. The case tells you the chord quality:
- Uppercase (I, IV, V) = major chord
- Lowercase (ii, iii, vi) = minor chord
- Lowercase with a small circle (vii°) = diminished chord
- Uppercase with a plus (III+) = augmented chord
So in C major, I-V-vi-IV means C, G, Am, F. In G major the same numerals mean G, D, Em, C. Same progression, same feeling, different key. That is the whole point: numerals describe the shape of a progression so you can move it anywhere.
These are standard conventions in music theory courses, for example in the Roman numeral lesson from Integrated Music Theory, which states that uppercase numerals have a major third and lowercase numerals have a minor third.
Step 1: number the notes of the scale
Take any major scale and number its seven notes. In C major that is:
C (1), D (2), E (3), F (4), G (5), A (6), B (7)
Now build a simple three-note chord (a triad) on each note, using only notes from the scale. Stack every other note: C, E, G on C. D, F, A on D. And so on. You get seven chords, and they always come out in the same pattern of major and minor:
| Numeral | Quality | In C major | In G major |
|---|---|---|---|
| I | major | C | G |
| ii | minor | Dm | Am |
| iii | minor | Em | Bm |
| IV | major | F | C |
| V | major | G | D |
| vi | minor | Am | Em |
| vii° | diminished | Bdim | F♯dim |
Memorize this one line and you can read most progressions: major keys go I, ii, iii, IV, V, vi, vii°. Major, minor, minor, major, major, minor, diminished. It works in all twelve major keys.
Step 2: minor keys work the same way
Most trap, drill and emotional rap beats sit in a minor key, so this part matters. Number the natural minor scale the same way. In A minor (A, B, C, D, E, F, G) you get:
| Numeral | Quality | In A minor | In C minor |
|---|---|---|---|
| i | minor | Am | Cm |
| ii° | diminished | Bdim | Ddim |
| III | major | C | E♭ |
| iv | minor | Dm | Fm |
| v | minor | Em | Gm |
| VI | major | F | A♭ |
| VII | major | G | B♭ |
Notice that A minor uses the exact same chords as C major, just starting from a different home chord. That is the relative major and minor relationship. The numerals change because the home chord (i or I) changes.
Why you sometimes see V instead of v in minor
In a lot of music, the fifth chord in a minor key is played as a major chord to make the pull back home stronger. In A minor that means E instead of Em. That raised note (G♯ instead of G) comes from the harmonic minor scale, so you'll see V or V7 in minor-key progressions like i-iv-V-i. If you want the full story, read the harmonic minor scale explained.
Step 3: translate a progression into any key
This is where numerals pay off. Find the key of your beat, write out the scale, and swap each numeral for the matching chord. Here are two of the most used progressions in modern music, written out in a few keys:
| Key | I-V-vi-IV |
|---|---|
| C major | C, G, Am, F |
| G major | G, D, Em, C |
| D major | D, A, Bm, G |
| F major | F, C, Dm, B♭ |
| A major | A, E, F♯m, D |
| Key | i-VI-III-VII |
|---|---|
| A minor | Am, F, C, G |
| C minor | Cm, A♭, E♭, B♭ |
| E minor | Em, C, G, D |
| F♯ minor | F♯m, D, A, E |
Don't want to write out scales by hand? The free chords by key page lists the chords that belong to every key, so you can read the numerals straight off it.
Progressions you'll see everywhere
- I-V-vi-IV: the classic pop loop. Bright, catchy, works for hooks.
- vi-IV-I-V: the same four chords starting on the minor one. Sounds more emotional.
- ii-V-I: the backbone of jazz, soul and a lot of R&B. In C major: Dm, G, C.
- i-VI-III-VII: a go-to minor loop for melodic rap and emotional trap.
- i-iv-v or i-iv-V: dark and simple, great for drill and trap where the 808 does the heavy lifting.
- i-VII-VI-VII: a moody back-and-forth loop that leaves lots of room for vocals.
Want to hear these right away? Open the free chord progression generator, pick a mood and key, and look at the numerals under each chord. Every progression it gives you comes with free MIDI you can drag into FL Studio, Logic Pro or Ableton.
Extra symbols: 7, ♭VII and V/V
Seventh chords
A 7 after the numeral means a seventh is added: V7 in C major is G7, ii7 is Dm7, Imaj7 is Cmaj7. If chord symbols like maj7 and m7 still feel fuzzy, check how to read chord symbols.
Flats and sharps in front of a numeral
A ♭ or ♯ in front means the chord's root is moved outside the normal scale. ♭VII in C major is B♭ instead of Bdim, and ♭VI is A♭. These are usually borrowed from the parallel minor key and give a progression that bittersweet, cinematic twist. More in borrowed chords explained.
Slash numerals like V/V
V/V reads as "five of five": the major chord that leads into V. In C major, V is G, and the five of G is D, so V/V is D major. These are called secondary dominants. See secondary dominants explained for examples you can try in a beat.
Small numbers like 6 or 6/4
In classical theory you may also see small numbers next to a numeral, like V6 or I6/4. Those describe inversions (which note is in the bass). Theory courses also use figures like 6/5, 4/3 and 4/2 for seventh chord inversions. For most beatmaking you can ignore these at first and just play the basic chord.
Roman numerals vs. the Nashville Number System
Session musicians, especially in country and gospel, often use the Nashville Number System instead. It is the same idea with regular numbers: 1, 5, 6, 4 instead of I, V, vi, IV. Minor chords are usually marked with a minus sign or a small m, like 6- or 6m. If you can read one system, you can read the other.
How to use numerals in your DAW
- Find the key of your beat or sample. Drop the file into Beat Lab to get an estimated key and BPM, right in your browser.
- Write out the seven chords of that key. Use the tables above or the chords by key page.
- Pick a numeral progression from the list above, or generate one with the chord progression generator.
- Swap numerals for chords and place them in your piano roll, one chord per bar to start.
- Change key without rewriting. If a vocalist needs it lower, keep the numerals and only change the key. The progression keeps its feel.
- Follow the roots with your 808. The root of each chord (C in C, A in Am) is a safe first note for your bass line.
Making beats for rappers and singers? Hear how these progressions sit under a vocal in the NameOnTheBeat beats.
FAQ
What does a lowercase Roman numeral mean in music?
A lowercase numeral is a minor chord. In C major, vi is A minor. Uppercase numerals are major chords.
What does the little circle (°) mean?
It means diminished. In major keys the vii chord is diminished, written vii°. In natural minor, ii° is diminished.
What is a I-IV-V progression?
It uses the first, fourth and fifth chords of a major key. In C major that is C, F and G. In G major it is G, C and D.
Is VI in a minor key the same as vi in a major key?
No. In A minor, VI is F major. In C major, vi is A minor. The numeral always counts from the home chord of the key you're in.
Do I need Roman numerals to make beats?
No, but they make it much easier to learn progressions from tutorials, copy the feel of a progression into another key, and talk about chords with other musicians.
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