A capo calculator that finds the easiest chord shapes
This capo calculator answers the two questions every guitarist with a capo asks. First: where should I put the capo for this song? Type the chords — or just choose the key — and every position from no capo to the 7th fret (or 5th or 9th) is ranked by how easy its chord shapes are, with diagrams you can tap to hear. Second: what am I really playing? Enter the shapes you finger and the fret the capo sits on, and the tool names the chords that actually sound.
Below both sits a full capo chart: the eight open shapes most players know (C, A, G, E, D, Am, Em and Dm) with the chord each one produces on frets 1 to 11. It works for standard tuning, drop D, DADGAD, open G, open D, open E, half-step-down tuning and for ukulele and baritone ukulele, all in your browser.
How to use the Capo Calculator
- Leave Best capo selected and type the song’s chords into Chords in the song, for example
Bb F Gm Eb. If you only know the key, clear the box and pick it under Song key. - Read the big answer — for that example, Capo 3 with G-major shapes (G, D, Em, C).
- Look down the ranking table for alternatives and press Show on any row to see its diagrams. Tap a diagram to hear the chord at the capo’s pitch.
- To go the other way, choose Shapes → chords, type the shapes and pick the fret under Capo on. The matching column of the capo chart lights up.
- Change Instrument and tuning for ukulele or alternate tunings, and Highest capo fret to allow higher positions.
Capo Calculator features
Ranked capo positions
Each fret is scored from the easiest generated voicing of every chord in the first five frets: open chords score well, full barres and stretches score worse, and higher capo positions get a small penalty.
Guitar chords with capo, both ways
From the song to the shapes (capo up, shapes down) and from the shapes to the sound (shapes up by the capo fret), with the key named both times.
Proper spelling
Results follow the key: a C shape with capo 3 sounds E♭, not D♯, and shapes in a minor song are spelled from the minor key.
Works from a key alone
With no chords entered, the main triads of the chosen key are used — I, ii, iii, IV, V and vi in a major key; i, III, iv, v, VI and VII in a minor key.
Hear every shape
Diagrams are strummed with Web Audio at the pitch they sound with the capo on; sound starts only when you tap and can be muted.
The maths behind a capo
A capo shortens every string by the same number of frets, and each fret is one semitone. So a shape played with the capo on fret n sounds n semitones higher than the same shape played open. The calculator uses that rule in both directions: sounding chord = shape + capo fret, and shape = sounding chord − capo fret, counting in semitones around the 12-note octave.
Worked example: a song in B♭ major uses B♭, F, Gm and E♭ — four barre chords in open position. Subtract 3 semitones and you get G, D, Em and C, four of the first chords anyone learns. That is why capo 3 comes out on top. Capo 1 (A, E, F♯m, D) is second: still open chords, but F♯m usually needs a barre.
| Song key | Easy shapes | Capo fret |
|---|---|---|
| A♭ / G♯ | G | 1 |
| A | G | 2 |
| B♭ | G | 3 |
| B | G (or A, capo 2) | 4 |
| C♯ / D♭ | C | 1 |
| E♭ | D (or C, capo 3) | 1 |
| F | E (or D, capo 3) | 1 |
| F♯ / G♭ | E (or D, capo 4) | 2 |
Choosing between good positions
The easiest shapes are not always the best sound. Higher capo positions give a brighter, more mandolin-like tone and shorter string lengths; lower ones keep the guitar’s body and bass. Two guitarists often split positions — one open, one with capo 5 or 7 — so the parts don’t overlap. Check that the melody still sits where you can sing it: the chord transposer moves a whole chord sheet to a better key first, and the guitar chord chart shows more voicings of each shape.
A capo pulls the strings slightly sharp. Put it just behind the fret, not on top of it, and check the tuning with the online tuner after fitting it.
Limits
- Key detection from chords alone is an estimate; if the key shown is wrong, choose it under Song key — it only changes how the shapes are spelled.
- Ease scores come from generated voicings, not from a survey of players. A chord you already know well may be easier for you than its score suggests.
- Partial and “cut” capos are not modelled; every string is assumed to be capoed.
- The capo chart lists only common open shapes. For any other shape use the second mode.
Capo Calculator FAQ
How does a capo calculator work?
It subtracts the capo fret, in semitones, from each chord of the song to get the shape you would finger, then rates how easy those shapes are. Doing this for every fret from 0 to 7 shows which position gives the friendliest chords.
What chord is a G shape with a capo on 2?
A. Each fret raises the shape by one semitone, so G becomes A on fret 2, B♭ on fret 3 and B on fret 4. The capo chart on this page lists the common shapes on frets 1 to 11.
Where do I put the capo to play in B♭?
Capo 3 with G-shape chords (G, C, D, Em) or capo 1 with A shapes (A, D, E, F♯m). Type B♭ F Gm E♭ and the calculator shows both, with diagrams.
Does a capo change the key of a song?
Yes — everything sounds higher by the number of frets. If you want the song in its original key, use the calculator in the first mode: it finds shapes that, with the capo, sound in the key you need.
Can I use this capo chart for ukulele?
Yes. Choose ukulele or baritone ukulele under Instrument and tuning; the ranking and diagrams use ukulele shapes. The capo chart itself (shape + fret = chord) works on any instrument.
Is anything sent to a server?
No. The calculations and the sound run in your browser.