Originally posted on Substack.
Try it out here if you like pressing buttons as much as I do! GitHub if you like reading code.
During the holidays, I wanted to get better at answering questions like “what is 7 half steps up from A?1” I often found myself in the situation of having these problems as a lot of guitar chord sheets are written something like “A capo 7” which means you put the big barre thing on your guitar and play an A-shape chord. When using a capo, the actual underlying chord is ‘A + 7 half steps’. This means if you’re collaborating with another instrument or with someone not using a capo, you need to communicate the actual chord you’re playing. This requires some mental math, which I found slightly embarrassing as I didn’t always immediately know what chord I was playing.