Ring size nightmare

I am trying to figure out what the ring sizes on the chart below would be in either US or UK sizing.
Have searched the internet and haven't come across any ring size chart that looks anything like this one.
Any help would be greatly appreciated.

Dana ♥

The Centenary Diamond
what exactly is it that you need to know?

Are you trying to figure out how the measurements match up to a standard ring size?

15mm is a standard US ring size 4¼ which is an H½ in the UK, and a 7½ in most Asian sizes.

So the ring size chart you're using there is in Asian sizing.