How Do You Find the Right Tire Size Before Buying Online?

Read the size off the tires currently on the car first, then check the sticker inside the driver's door. The door sticker shows the factory size, but if the vehicle has aftermarket rims, the tires on it may be a different size entirely.

Most guides tell you to check the door sticker and stop there. That is the step that gets people the wrong tires.

Where do you find your tire size?

In two places, and the order matters. The sidewall of each tire on the vehicle tells you what is fitted right now. The sticker inside the driver's door jamb tells you what the manufacturer specified when the vehicle was built. Start with the tires.

The first thing we recommend before buying tires is to look at the tires that are actually on the car, not just the door. The reason is that some cars have aftermarket rims and are running a different size than the factory one. You want to match the rims with the tires. Then the second thing is to open the door, and there is a sticker inside that shows the factory size for your vehicle. You can also look up your vehicle and rim size online and usually get it right. But if you are not sure, give us a call and we can take a look ourselves, or drop by the shop and we will tell you exactly which size it is.

The three ways to check, in order

1. Read the sidewall on the tires currently fitted. This is what your rims are actually wearing.
2. Open the driver's door and read the sticker on the jamb. This is the factory specification, plus your recommended pressures.
3. Look it up online by vehicle and rim size, as a cross-check.

If all three agree, you are done. If they do not, keep reading.

And if the tire on the car right now has a puncture rather than a sizing mismatch, that's a repair question, not a buying one.

What if the door sticker and the tires do not match?

Someone changed the size, and the usual reason is aftermarket rims. A different rim diameter or width needs a different tire size to work. If you are keeping those rims, the tire has to fit the rims you own, not the ones the vehicle left the factory with.

Why this happens

• Aftermarket rims in a different diameter or width
• A plus-size or minus-size setup done deliberately by a previous owner
• A winter setup on smaller rims, which is common and usually intentional. See whether a second set of winter rims is worth it
• Someone previously fitted the wrong size and it stuck

The door sticker is still useful even when it disagrees, because it gives you the load index and the recommended inflation pressures your vehicle needs. Those requirements do not change just because the rim did.

How do you read the size once you find it?

Buying for winter specifically? check winter tire sizing on our Fredericton page before you order.

There is a fuller walk-through in how to read tire size on the sidewall. A size reads like 225/65R17 98H. The 225 is the width in millimetres, the 65 is the sidewall height as a percentage of that width, R means radial, 17 is the rim diameter in inches, 98 is the load index, and H is the speed rating.

What each part has to match

The load index is the one that gets skipped, and it is the one that matters most for safety. A tire can fit your rim perfectly and still be rated to carry less weight than your vehicle puts on it.

What goes wrong when people order online?

Two things, mostly. The wrong size, because they read the door sticker on a vehicle running aftermarket rims instead of checking what is actually mounted. And the wrong load rating, because the size printed looked right and nobody checked the number that comes right after it, the part that tells you how much weight the tire can safely carry.

Both cost the same thing: four tires that arrive and cannot be fitted, and a return process that eats a week you did not budget for during changeover season.

Check these before you pay

• The size matches the rims on the vehicle, confirmed from the sidewall
• The load index is at or above the door sticker figure
• The speed rating suits the vehicle
• All four tires are the same make, model, and size
• The build date is recent. The last four digits of the DOT code are the week and year
• If the tires will run in winter, the 3PMSF snowflake is on the sidewall

What if you are still not sure?

Call us or come by. Confirming a tire size takes us a couple of minutes and costs nothing, and it is a lot less painful than four wrong tires showing up at your door. Over the phone we can often sort it out from the numbers you read to us, or we will read it straight off the vehicle ourselves.

Once the size is confirmed, Fredericton tire change pricing for the fitting is posted so you know that number too.

Phone (506) 248-6006, or drop in at 300 Wilsey Road #1, Fredericton. We are open seven days a week, Monday to Saturday 9 to 7 and Sunday 9 to 5. If you would rather we handle the whole thing, we order tires through our supplier catalogues and book the fitting for when they arrive.

Key takeaways

• Check the tires on the vehicle first, then the door jamb sticker.
• The two disagree when a vehicle has aftermarket rims, and the rims win.
• The door sticker is still the source for load index and correct pressures.
• Load rating is the most commonly missed spec. Never go below factory.
• Confirm size, load, speed rating, matching set, build date, and the snowflake before paying.
• We will read the size off your vehicle at no charge, by phone or in the shop. Confirming a tire actually fits still needs the vehicle in front of us.

Frequently asked questions

Where is the tire size on my car? Two places. Moulded into the sidewall of each tire, and on a sticker inside the driver's door jamb. The sidewall tells you what is on the vehicle right now. The door sticker tells you what the manufacturer originally specified. Check both, because they can differ.

What if the door sticker and my tires say different sizes? Someone changed the size at some point, usually because the vehicle has aftermarket rims. Match what is physically on the car if you are keeping those rims, because the tire has to fit the rim you own, not the rim the factory fitted.

What do people get wrong when ordering tires online? The two we see are the wrong size and the wrong load rating. Size is the obvious one. Load rating is the quieter mistake, because a tire that fits the rim can still be rated to carry less weight than your vehicle needs.

Can you help me confirm my tire size? Yes, and there is no charge for it. Call (506) 248-6006 and we can usually sort it out over the phone, or drop by 300 Wilsey Road #1 and we will read it off the vehicle for you. Better than guessing and having four wrong tires arrive.