How to read the numbers on the side of your tyre
A tyre size like 205/55R16 91V reads as: 205 is the tread width in millimetres, 55 is the sidewall height as a percentage of that width, R means radial construction, 16 is the rim diameter in inches, 91 is the load index, and V is the speed rating. The load index and speed rating must be at least what the vehicle manufacturer specifies.
Everything you need to order the right tyre is moulded into the sidewall. Once you know the pattern it takes about five seconds to read.
Working through 205/55R16 91V
- 205 — the width of the tread in millimetres
- 55 — the profile: the sidewall height as a percentage of the width, so 55% of 205mm, about 113mm
- R — radial construction, which is essentially every modern car tyre
- 16 — the rim diameter in inches, which is why this number is the one that must match your wheel exactly
- 91 — the load index, a coded maximum weight per tyre
- V — the speed rating, a coded maximum sustained speed
Where to find the right size for your car
Two places. The tyre placard — usually in the driver's door opening, sometimes inside the fuel filler flap or the glovebox — lists the sizes and pressures the manufacturer specifies. And the sidewall of what is currently fitted, though that only helps if someone has not already fitted the wrong thing.
If those two disagree, the placard is the one to trust.
The other markings
- A four-digit DOT code giving the week and year of manufacture — 3223 means week 32 of 2023
- Tread wear indicators, marked around the shoulder, showing where the 1.5mm bars sit
- Rotation arrows on directional tyres, which must point the right way when fitted
Ring the workshop with the numbers off your sidewall and we can tell you what is in stock, new or second-hand, before you drive over.
A Grade Tyre & Auto handles this at the workshop on Lawrence Drive, Nerang.
General information only, current as at 11 September 2026. Requirements change and individual circumstances differ — for anything that turns on your specific situation, check with Queensland Department of Transport and Main Roads on 13 23 80 or at qld.gov.au.