Thinking about selling my rims. Could anyone give me some insight on how to calculate tire percentages? Or do people just do a rough estimate?

 

You can get a fancy guage to measure the remaining thread, or use 26 cents

http://www.tirerack.com/tires/tirete....jsp?techid=51

When selling tires people sometimes mention now many 32ths are left, and the above gives you an idea what that is...

I think most people just guess when posting percentages

 

Go to a tire shop and ask to have them use a tread depth gauge on your tires, take the lowest number and divide that by what the tire came with new and that's what percentage of tread you have left...

Or you can just use common sense and guess