Tire size comparison calculator
Compare two sizes such as 225/65R17 and 235/60R18: overall diameter, sidewall, revs per mile, and how far your speedometer would be off.
Open the calculator →Free tire tools
Simple calculators that run in your browser. Nothing you type is sent or saved.
DOT date code decoder
Type the last four digits of the DOT code on your sidewall to see the week and year it was made and how old the tire is today.
Open the decoder →More tools are on the way. Meanwhile, see all tire guides.