How to use it
- Choose the direction. Chords → numbers makes a number chart from a song; numbers → chords turns a number chart into chords.
- Paste your chart. A chord list, a song with chords above the lyrics, or lines of numbers. Bar lines and lyrics stay where they are.
- Check the key. For chords → numbers the key is detected from the chords; change it if the song is in another key. For numbers → chords, pick the key to play in.
- Copy the result or open the chords in the transposer to change the key, add a capo or print a chord sheet.
How the Nashville Number System works
Each chord is written as the number of its root in the major scale of the key. In the key of G, the scale is G A B C D E F♯, so G is 1, C is 4 and D is 5. A number on its own means a major chord; "m" (or a minus sign) makes it minor, and "°" diminished. Change the key and the numbers stay the same: 1 4 5 is G C D in G and A D E in A.
| Key | 1 | 2m | 3m | 4 | 5 | 6m | 7° |
|---|---|---|---|---|---|---|---|
| C major | C | Dm | Em | F | G | Am | B° |
| G major | G | Am | Bm | C | D | Em | F♯° |
| D major | D | Em | F♯m | G | A | Bm | C♯° |
| A major | A | Bm | C♯m | D | E | F♯m | G♯° |
| E major | E | F♯m | G♯m | A | B | C♯m | D♯° |
| F major | F | Gm | Am | B♭ | C | Dm | E° |
| B♭ major | B♭ | Cm | Dm | E♭ | F | Gm | A° |
| E♭ major | E♭ | Fm | Gm | A♭ | B♭ | Cm | D° |
Worked example
A song in G uses G, Em, C and D. As numbers that is 1 6m 4 5. If the singer wants it in A, read the same numbers in A: A, F♯m, D and E. Nobody has to rewrite the chart.
Symbols you'll see on a number chart
- m or −: minor (6m, 2m).
- °: diminished (7°).
- Slash: a bass note, as a scale number: 1/3 is the 1 chord with the 3rd in the bass (G/B in G).
- ♭ or ♯ before the number: a chord on a lowered or raised note: ♭7 in G is F.
- Other chord types use the usual chord-symbol signs after the number, such as 4maj7 (or 4Δ) and 2m7. This converter writes a dominant 7th as 5(7), so it can't be misread as "57".
The symbols are not completely standardized, so charts from different players can look a little different.
Minor keys
Charts for minor-key songs more often count from the relative major key. A song in A minor is numbered in C: Am = 6m, B° = 7°, C = 1, Dm = 2m, Em = 3m, F = 4, G = 5. Some players count from the minor home chord instead (Am = 1m). The converter does both: pick "Minor keys" when the key is minor.
Where it comes from
Neal Matthews Jr. of the Jordanaires began writing parts with numbers in Nashville in the late 1950s. Session musician Charlie McCoy adapted the idea for the rhythm section in the early 1960s, and the system later spread to musicians far beyond Nashville.