You choose an original key and a capo fret position. Each fret raises pitch by one semitone (half step). The tool subtracts the capo's semitone offset from each chord's root note to find the chord shape you need to play. It uses the standard 12-note chromatic scale (C, C#, D, ... B) and transposes common open-position chords — C, Dm, E, Em, F, G, A, and Am.
A capo lets you play open-position chord shapes in any key, which often sound fuller and ring out more naturally than barre chords. It is especially popular in folk, country, and singer-songwriter styles where open strings are part of the sound.
Not the tuning of the individual strings relative to each other — it raises all strings by the same number of semitones. The intervals stay the same, so chord shapes work identically. It is effectively like having a shorter-scale guitar tuned higher.
The 12th fret is one full octave. Going higher is physically impractical on most guitars because the frets are too close together and tone quality drops. If the chart doesn't show your key, try transposing in the other direction or using barre chords.
The semitone math is universal, but the chord shapes shown here are for standard 6-string guitar tuning (EADGBE). Ukulele and banjo use different tunings, so the shape names and fingerings would be different.
Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.