One sharp (F♯). On guitar this is home base: G, C, D and Em are the first four chords most people learn, and they cover an alarming number of songs.
| Chord | Number | Roman |
|---|---|---|
| G | 1 | I |
| Am | 2m | ii |
| Bm | 3m | iii |
| C | 4 | IV |
| D | 5 | V |
| Em | 6m | vi |
| F♯dim | 7° | vii° |
The 1, 4 and 5 (G, C, D) are the backbone. Add the 6m (Em) and you can play most of what's on the radio. The 7° (F♯dim) mostly shows up as a passing chord, so don't lose sleep over it.
Those numbers are the Nashville number system. Learn the progression as numbers once and it works in every key.
No capo, G shapes; capo 3, play E shapes; capo 5, play D shapes; capo 7, play C shapes.
The capo chart has every key, and the transpose chart moves a song somewhere else entirely.
Songs that leave G usually go to its 4 or 5: key of C or key of D. Or see every key.
Chartless listens to whatever is playing and shows the key, the chords and the numbers live, so you can check a recording against this page while it plays. How to find the key by ear if you'd rather do it yourself.