Tire size explained — by size

Sidewall code walkthroughs for 748 tire sizes — width, aspect ratio, rim diameter, overall diameter, sidewall height, and which vehicles use each size as OEM.

Each page decodes the size string digit-by-digit, draws the sidewall to scale, lists every vehicle that uses the size as OEM, and links to the /upsize/ page for safe alternatives.

R12

135/80R12 145/70R12 145/80R12 155/70R12 155/75R12 155/80R12 165/60R12 165/70R12

R17

135/50R17 135/70R17 135/80R17 135/90R17 145/70R17 145/90R17 155/90R17 165/90R17 175/65R17 175/90R17 185/50R17 195/40R17 195/45R17 195/50R17 195/55R17 195/60R17 205/40R17 205/45R17 205/50R17 205/55R17 205/60R17 205/65R17 205/70R17 215/35R17 215/40R17 215/45R17 215/50R17 215/55R17 215/60R17 215/65R17 215/70R17 225/35R17 225/40R17 225/45R17 225/50R17 225/55R17 225/60R17 225/65R17 225/70R17 225/75R17 225/80R17 235/40R17 235/45R17 235/50R17 235/55R17 235/60R17 235/65R17 235/70R17 235/75R17 235/80R17 245/40R17 245/45R17 245/50R17 245/55R17 245/60R17 245/65R17 245/70R17 245/75R17 255/40R17 255/45R17 255/50R17 255/55R17 255/60R17 255/65R17 255/70R17 255/75R17 255/80R17 255/85R17 265/40R17 265/60R17 265/65R17 265/70R17 275/35R17 275/40R17 275/45R17 275/55R17 275/60R17 275/65R17 275/70R17 275/80R17 285/40R17 285/65R17 285/70R17 285/75R17 295/35R17 295/70R17 305/45R17 305/65R17 305/70R17 315/35R17 315/55R17 315/60R17 315/70R17 335/35R17

R18

135/80R18 155/85R18 175/60R18 195/50R18 195/55R18 195/60R18 205/35R18 205/40R18 205/45R18 205/50R18 205/55R18 205/60R18 215/35R18 215/40R18 215/45R18 215/50R18 215/55R18 215/60R18 215/65R18 215/85R18 225/35R18 225/40R18 225/45R18 225/50R18 225/55R18 225/60R18 225/65R18 235/30R18 235/35R18 235/40R18 235/45R18 235/50R18 235/55R18 235/60R18 235/65R18 235/70R18 235/80R18 245/35R18 245/40R18 245/45R18 245/50R18 245/55R18 245/60R18 245/65R18 245/70R18 245/75R18 255/35R18 255/40R18 255/45R18 255/50R18 255/55R18 255/60R18 255/65R18 255/70R18 265/35R18 265/40R18 265/45R18 265/55R18 265/60R18 265/65R18 265/70R18 275/35R18 275/40R18 275/45R18 275/55R18 275/60R18 275/65R18 275/70R18 285/30R18 285/35R18 285/40R18 285/45R18 285/50R18 285/55R18 285/60R18 285/65R18 285/70R18 285/75R18 295/30R18 295/35R18 295/40R18 295/45R18 295/65R18 295/70R18 305/30R18 305/35R18 305/40R18 305/45R18 305/60R18 305/65R18 305/70R18 315/30R18 315/40R18 315/70R18 325/35R18 325/45R18 325/60R18 325/65R18 335/30R18 345/35R18

R23

255/40R23 275/35R23 275/40R23 285/35R23 285/40R23 295/35R23 305/35R23 305/40R23 315/25R23 315/30R23 325/30R23 325/35R23 335/30R23

R24

255/30R24 275/25R24 275/50R24 285/35R24 285/40R24 295/30R24 295/35R24 295/40R24 295/45R24 305/35R24 315/35R24 315/45R24 315/50R24 325/45R24 335/30R24 345/50R24 355/40R24 375/40R24 385/35R24

R26

295/25R26 295/30R26 305/30R26 315/40R26 385/30R26

R28

295/25R28 325/35R28

R30

Looking for which cars take a given size? See the tire size reverse lookup.