Tab follows the key

Change the key (or set a capo) and any tab in the song moves with it — the fret numbers shift by the same amount as the chords, so a riff stays in tune with the song.

A fret is a semitone, so it's just adding to each number, but the columns stay lined up even when a single-digit fret becomes two digits.

A few musical details:

• It moves the shortest way — a semitone down is −1 fret, not eleven frets up the neck.
• If a note would drop below the open string, it's lifted an octave so it stays playable rather than showing a negative fret.
• An octave change is a no-op, and it works for guitar and 4/5/6-string bass.

If a pasted tab block is too mangled to read, it's left exactly as-is rather than risk breaking it.