Where to Find Your Tyre Size
Your tyre size is written in two places, so you almost can't miss it. The easiest spot is on the tyre itself. The other spot is a sticker inside your car that tells you the size the manufacturer recommends.
On the Tyre Sidewall
The outer wall of every tyre, the part you can see from outside the car, has a row of numbers and letters printed or raised into the rubber. That's your tyre size.
Inside the Driver's Door
Open the driver's door and look at the door frame or door pillar, the part you see when the door is open. There's a sticker with the correct tyre size for your car.
In the Owner's Manual
Every car comes with a manual, usually kept in the glovebox. It lists the correct tyre size under a section called "tyres" or "wheels and tyres."
Inside the Fuel Flap
Some cars, especially older models, print the tyre size on a small sticker inside the fuel filler flap instead of the door frame.
How to Read Tyre Size Numbers
Tyre size looks like a strange code at first, something like 205/55R16 91V, but each part simply describes one measurement. Once you know what each number means, reading it becomes as easy as reading a shoe size.
Width (205)
How wide the tyre is in millimetres, measured from sidewall to sidewall.
Profile / Aspect Ratio (55)
The height of the sidewall, shown as a percentage of the width. Here, the sidewall is 55% as tall as the tyre is wide.
Construction & Rim Size (R16)
"R" means radial construction, the standard on almost every modern car. "16" is the wheel rim diameter in inches.
Load Index (91)
A code number showing the maximum weight the tyre can safely carry. Higher numbers mean a higher weight limit.
Speed Rating (V)
A letter showing the maximum safe speed for the tyre. It's a safety limit, not a target speed.
Put simply: 205/55R16 91V means a tyre that's 205mm wide, with a sidewall height equal to 55% of that width, built to fit a 16 inch rim, able to carry up to its rated load, at up to its rated speed.
Try It Yourself: Tyre Size Tool
Already know your code? Decode it instantly below. Only know your rego? Send it straight to us and we'll confirm your tyre size for free.
No tools, no guesswork — pick whichever you have on hand.
That doesn't look like a tyre code yet — try something like 205/55R16.
Not sure what to type? It's printed on your tyre sidewall or the sticker inside the driver's door.
Enter your plate number first.
We'll look up your correct tyre size and confirm it free of charge — no obligation.
Opening your email app with the plate filled in — just hit send.
Step by Step: Find Your Tyre Size in 3 Steps
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Open the driver's door
Stand next to the driver's seat and open the door all the way, so you can see the door frame where the door normally closes shut.
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Look for the white or yellow sticker
Somewhere on that frame, usually around waist height, there's a sticker with several rows of small text and numbers. Look for the row labelled "tyre" or "tire."
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Read the code left to right
You'll see something like 205/55R16. That's your tyre size, in the exact order: width, profile, construction, rim size. Write it down or take a photo with your phone.
Common Mistakes to Avoid
| Mistake | Why it matters |
|---|---|
| Reading the size off a spare tyre | Space-saver spares are often a completely different size to your normal tyres |
| Mixing up two different tyre sizes on one car | Some cars use a different size at the front to the back, always check each tyre individually |
| Ignoring the load index and speed rating | Two tyres can share the same width and rim size but carry different weight and speed limits |
| Guessing instead of checking | The wrong size can affect handling, fuel use, and how accurate your speedometer reads |
Not Sure You've Got It Right?
Send us a photo of your door sticker or tyre sidewall, or just give us your rego, and we'll confirm your exact tyre size for free.
Tyre Size FAQs
Where exactly is the tyre size written?
On the outer sidewall of every tyre, and on a sticker inside the driver's door frame. Some cars also print it inside the fuel flap or in the owner's manual.
What do the numbers 205/55R16 actually mean?
205 is the tyre width in millimetres, 55 is the sidewall height as a percentage of that width, R means radial construction, and 16 is the rim diameter in inches.
Can I just use the size on my current tyre?
Usually yes, as long as it's an original-fit tyre and not the space-saver spare. If your current tyres don't match the door sticker, always trust the door sticker.
Do all four tyres have to be the same size?
Not always. Most cars use one size all round, but some performance and sports cars fit a wider size at the rear than the front. Always check each tyre.
What if I still can't find my tyre size?
Call Auckland Tyres on 09 622 2727 with your car's registration plate, and we'll look up the correct size for you free of charge.