Free Tool
Tire Size Decoder
Type the size printed on your sidewall — like 180/55ZR17 M/C 73W — and we'll break down what every number and letter means.
Find it on your sidewall, e.g. 120/70ZR17.
We decode the structure of your size — width, aspect ratio, construction, and rim. Load-index and speed-rating codes are shown as codes; match them to your bike's spec on a standard chart. Always confirm fitment before buying.