Let’s say you wanted to figure out angles based on a desired arc length and radius, the math is nasty.

Alternately, you can go here:

https://www.omnicalculator.com/math/arc-length

Yeet! Angles everywhere.

Alternately, for a given angle and radius you can determine the arc length.

It’s highly specialized, but it sure helped me out for this really specific thing I am doing. I haven’t explored, but they have a lot of other calculators. Let’s see… Oh wow, there are a lot. You’ll just have to poke around.