One problem I have with creating rings with Tinkercad is that I can easily find the circumference of the ring, but not the diameter. While taking metalworking classes in college, I learned that knowing diameter and the circumference is important for a proper fit. What are the rings above based on? I copied the above template and it seems off.
This is why I created this template, so same color rings are those US ring sizes as the number tells. If you want to know the diameter in mm, then just click the number "plates" active and it will show the size. If you have payed plan, then here's one example of Shape Script to handle also the inner diameter:
First stab at constant diameter ring