[klodolph]

The spacing of the black keys is so far from the actual spacing on a real keyboard that I question how it could possibly look right to you. I would love to know if you actually have a real physical keyboard on hand, like I do, or if you are just going based on memory.

[robbrown451]

You should check out google images for piano key clip art. Almost all of them get it wrong. They assume a black key is centered between two white keys, but that is only true for g#.

The width of all keys, white or black, should be equal to one another at the back of the keyboard.

The width of the white keys should be exactly equal to one another at the front of the keyboard.

Those can't both be true (since 5/12 isn't equal to 3/7), so the former has to be fudged a bit.

My formula is in a different comment. :)

[userbinator]

For some reason, this reminds me of "What happens when you ask people to draw a bike": https://news.ycombinator.com/item?id=17699017

The black and white keys are instantly recognisable as a piano, but need a bit more inspection to notice the error.

[robbrown451]

Interesting. Some people got the bike right. I'm quite sure I can draw a proper bike, but I have a long history in drafting and mechanical design.

[noduerme]

Literally just came across this thread after playing piano for the last couple hours, and I wouldn't have noticed it if it weren't pointed out. I think when you play you're just used to seeing all kinds of shorthand. I remember portable synthesizers from the 80s that actually did have this kind of relative size on black keys.