How to Read Your Tire Size in Staten Island

Every tire carries its own spec sheet, molded right into the sidewall. Once you know how to read it, buying tires stops being guesswork: you can compare options on your own, spot a wrong size before it goes on your car and ask the right questions at the counter. This guide walks you through each part of the code, using the kind of tires we mount every day at Speed Auto World on Forest Avenue in Staten Island.

Where to find your tire size

Start in two places:

• The driver's door jamb. Open the driver's door and look for a white and yellow sticker (the tire and loading information placard). It lists the original tire size and the recommended cold inflation pressure.
• The sidewall of your current tires. The size is the largest string of numbers and letters, something like 225/45R17 94V.

If the two do not match, trust the door placard first. Used cars sometimes come with tires a previous owner chose, and they are not always the right ones.

How to read tire size, step by step

Take a common example: 225/45R17 94V.

Width: 225

The first number is the section width in millimeters, measured from sidewall to sidewall. A 225 tire is about 225 mm wide. Wider is not automatically better; it can change steering feel and rub on tight wheel wells.

Aspect ratio: 45

After the slash comes the aspect ratio: the sidewall height as a percentage of the width. Here the sidewall is 45% of 225 mm, about 101 mm. Lower numbers mean shorter sidewalls, sharper handling and a firmer ride. Higher numbers mean more cushion, which helps on rough streets.

Construction: R

R means radial, the construction used on virtually every passenger car and SUV today.

Rim diameter: 17

The number after the R is the rim diameter in inches. This one is not negotiable: a 17-inch tire only fits a 17-inch rim. Some commercial trucks use half sizes such as 19.5.

Load index and speed rating: 94V

• 94 is the load index, a code for the maximum weight each tire can carry at its rated pressure. 94 corresponds to 670 kg (1,477 lb) per tire.
• V is the speed rating, the maximum sustained speed the tire is designed for.

Never go below the load index on your door placard. With speed ratings, matching the original is the safe default.

Quick reference table

The DOT code: how old is the tire?

Near the rim you will find a code that starts with DOT. Under federal rules (49 CFR § 574.5), its last four digits show the week and year of manufacture. 2423 means week 24 of 2023. People often read the first two digits as a month; they are a week.

Rubber ages even when a tire sits unused, so the date matters, especially on spare tires and on used tires. Ask your installer to check the date before anything is mounted.

You can also enter the full tire identification number in the NHTSA recall lookup to see whether it has an open recall.

Other sidewall markings worth knowing

• M+S or the three-peak mountain snowflake symbol. M+S means the tread was designed for mud and snow. The mountain snowflake marks tires that passed a standardized snow traction test, which is the better signal for real winter performance.
• XL or Extra Load. A reinforced tire that carries more weight at higher pressure. Common on SUVs and some sedans.
• Treadwear, traction and temperature grades (UTQG). For example 400 A A. Useful to compare tires within the same brand.
• Maximum pressure. This is the tire's limit, not the pressure you should run. Use the number on your door placard.

Choosing the right tires for Staten Island and NYC driving

Reading the size is half the job. The other half is matching the tire to how you drive.

Think about the roads you actually use

Daily driving here mixes stop-and-go traffic on Hylan Boulevard and Richmond Avenue, expressway runs on the Staten Island Expressway and the Verrazzano, and plenty of potholes after a hard winter. Very low-profile tires look sharp but have less sidewall to absorb a pothole hit, which puts more stress on both tire and rim. If comfort and durability matter more than sporty handling, staying with the original aspect ratio is usually the smartest move.

Plan for winter

New York winters bring snow, slush and freezing rain. All-season tires work for many drivers who stick to plowed roads. If you commute early, drive hills or cannot stay home on snow days, ask about tires with the three-peak mountain snowflake symbol.

Replace in pairs or sets

Mismatched tread depth affects braking and stability, and many all-wheel-drive vehicles need all four tires within a close tread depth. If you only replace two, the newer tires usually go on the rear axle. Ask us what makes sense for your vehicle.

New or used?

Quality used tires can be a smart way to stretch a budget, as long as they are checked for depth, age and damage. Brand new tires give you the full tread depth and a known history from day one. We carry both, so you can compare side by side. Pricing and availability change often, so ask in the store or call.

About the New York State tire fee

When you buy a new tire in New York, the state applies a waste tire management fee of USD 2.50 per tire, which funds the cleanup and recycling of scrap tires. It does not apply to used tires. Source: New York State Department of Taxation and Finance, Waste Tire Management and Recycling Fee.

Common mistakes to avoid

1. Buying by rim size alone, without checking width and aspect ratio.
2. Choosing a lower load index to save money.
3. Inflating to the "max pressure" on the sidewall instead of the door placard.
4. Ignoring the DOT date on a tire that looks new.
5. Mixing very different tread patterns on the same axle.

Get the right fit at Speed Auto World

Bring us your size, a photo of your sidewall, or just the car. Our team at 2409 Forest Ave, Staten Island, NY will confirm the correct size, show you new and used options and handle mounting and balancing.

• Browse what we have: see our tires
• Reserve your time for mounting and balancing: book an appointment
• Stuck with a flat anywhere in Staten Island or nearby: request roadside assistance

Questions? Call 929-989-0002. Store hours: Monday–Friday 8 AM–8 PM, Saturday 8 AM–6 PM, Sunday 9 AM–6 PM. We speak English and Spanish (se habla español).