Capo Calculator
Find the best capo fret and the easy chord shapes for any song — or turn capo shapes back into real chords.
MusoKit's capo calculator is a free online tool that finds the best capo position for any song. Type the chords as written and it shows which fret to put the capo on and which easy open shapes (like G, C, D, Em) to play instead — or convert capo shapes back into the real sounding chords. Every capo fret raises the pitch by one semitone. No signup or download.
How to use
- Type or paste the song's chords — for example Bb Gm Eb F — or tap one of the examples.
- Check the Best capo positions cards. They rank every fret by how many of the resulting shapes are easy open chords. Tap one to select it.
- Read the shapes to play: with the capo on, finger these shapes and the song sounds in its original key.
- Hit Play progression (or tap any chord) to hear how it sounds.
- Already know the shapes from a chord sheet that says "Capo 3"? Switch to Capo shapes → real chords to see what's actually sounding — handy for playing along with a keyboard or bass player.
How capo math works
A capo clamps across all six strings and acts like a new nut. Every fret you move it up raises the pitch of everything you play by one semitone. So a G shape with the capo on fret 2 sounds as A, and a C shape on fret 5 sounds as F.
To go the other way — from the song's real chords to the shapes you'll play — you subtract the capo fret. A song in Bb with the capo on fret 3 becomes G shapes (Bb − 3 semitones = G), so Bb Gm Eb F turns into the friendly G Em C D.
The "best" position isn't just the lowest fret. The calculator scores each fret by how many of the shapes are easy open chords (C, A, G, E, D, Am, Em, Dm and their common 7th and sus variants), counts barre chords like F and Bm as medium, and gently penalises positions above fret 7 where the neck gets cramped and the tone gets thin.
FAQs
What does a capo do?
A capo clamps down all the strings at one fret, shortening them so every note rises by one semitone per fret. It lets you play songs in any key using easy open chord shapes, and it's also used to match a singer's range or to get the bright, ringing sound of open strings higher up the neck.
How do I find the right capo position for a song?
Enter the song's chords above. The calculator transposes them to every capo fret from 0 to 9 and ranks the positions by how easy the resulting shapes are. For most songs in flat keys (Bb, Eb, F, Ab) the answer is capo 1–3 with G, C or D shapes.
What key am I in with a capo on fret 2 playing G shapes?
A major. Each fret adds a semitone: G + 2 semitones = A. Use the capo chart above to read any combination — find your shape in the left column and your capo fret along the top.
Do I call the chords by their shape or by their real name?
Both are common. Chord sheets usually write the shapes and add "Capo 3", because that's what the guitarist fingers. When you talk to a keyboard player, bassist or singer, use the real sounding chords — that's what they'll play or sing along to.
Does a capo work on ukulele, banjo or mandolin?
Yes — the math is identical on any fretted instrument: one fret equals one semitone. The shape-easiness ranking here is tuned for guitar open chords, but the transposition and the capo chart work for any instrument.