How To Measure Tires
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Want the Best Tires? Here’s How to Measure Tires Like a Pro Before You Buy!
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Most people have probably never thought about measuring tires. Not that could either be because they are familiar with the numbers on the tire’s sidewall, have access to the old tire’s owner manual or like most people have no idea how to measure. So, if you were to ever measure your tires, how’d you do that. Don’t worry, though. We’re here to guide you through the process and the different ways you can measure your tire (if you ever have to!!!)
Why Measure Tires?
Well, for one, you need your tire size when you have to buy new tires. Pretty obvious huh!!
But we can’t count the number of customer stories where they had to order a tire and went with their local tire store just because they didn’t want to measure their tires only later regretting the same tire available for a much better deal online. Now that you’ve probably heard of!!!
You don’t need to measure tires just when you are buying new ones. You tire size also shows you what other sizes you can accommodate, specially when you are handling snow, tough terrains or off-road journeys.
And measuring tires is simple. We’ll share multiple ways to measure a tire and if one works for you, then don’t waste time reading the other ones (if you don’t have to!!!).
Method-1: Read Your Tire’s Sidewall or Owner’s Manual
Easiest way, read your tire’s sidewall.
Here’s an example: 225/65R17 102H. Let’s learn to read this:
- 225: tire width in millimeters
- 65: is aspect ratio. What is the height of the tire’s sidewall expressed as a percentage of the tire’s width. In this case, the sidewall height is 65% of 225mm.
- R: This stands for Radial, which tells you the tire’s construction. Most tires today are radial, meaning the internal layers run radially across the tire.
- 17: This is the wheel diameter, measured in inches. It’s the size of the wheel that the tire will fit on.
- 102H: Load Index (how much load can the tire take) and Speed rating (top speed your car can reach). In this case, 102 refers to almost 1874 pounds and H refers to 130 mph. You can find these reference values easily online.
If you can find these number either on the sidewall or in the owner’s manual, then you’re good to go.
Pro Tip: There is also a placard on the inside of the driver’s side door that lists recommended tire sizes and pressures.
If you still can’t find the size, let’s jump to manual measurements.
Method-2: Measuring Tires Manually
You’ll need these to start with
Measuring Tape or Ruler: Preferably one that measures in both millimeters and inches.
- Tire Gauge: If you’re also planning to check tread depth, a tire gauge will come in handy.
- Pen and Paper/Digital Notes: for the obvious note taking
Now let’s start measuring
Step 1: Measuring Tire Width
Park you car on a flat surface with properly inflated tires.
Measure using the tape from one sidewall to another. Make sure you’re measuring at the widest point, not where the tire meets the road.
If your measurement comes to something like 225mm, then you’ve got the tire width.
Step 2: Measuring Aspect Ratio
Now, the aspect ratio isn’t something you’ll measure yourself but something that you’ll calculate.
To calculate the Aspect Ratio just find the value of the percentage. Example, for a 225/65 tire, the sidewall height is 65% of 225mm, which equals 146.25mm.
If you don’t like a lot of math, just check tire’s sidewall, and you’ll find it there.
Step 3: Measuring Wheel Diameter
This is easy.
With your tape measure the diameter of the wheel (not the tire) from one end to the other.
This value in inches is your tire diameter.
Step 4: Checking Tread Depth
If you’re buying used tires, you always want to measure tread depth. You get started with your tire gauge.
Insert the gauge into the tread and press until the shoulders of the gauge lie flat against the tread. The depth will be displayed on the gauge.
In U.S., the legal minimum tread depth needed is 2/32 of an inch, but you’ll want more than that for a safe drive.
Seasonal Factors Based Measurement:
If you live in an area with harsh winters or scorching summers, you might need different tires for different seasons.
– Winter Tires: have a higher aspect ratio to handle snow and ice better
– Summer Tires: have lower aspect ratios for increased grip
When can you Deviate from Manufacturer Recommendations:
Sometimes you might want or are forced to go with a different tire size when you’re looking for better performance or off-road capability. Here’s when it might a little flexible:
– Performance Upgrades: Wider tires give better grip, but you’ve got to ensure they’ll fit without rubbing.
– Off-Roading: Taller tires help with clearance but there should be enough space.
And like that you are a pro at measuring tires. But if you have any doubts whatsoever, just consult a tire professional- a local shop or online customer service. Better to be sure than worry!!!
Conclusion
Measuring tires is easier than you thought. Most of the times just looking at your sidewall is enough. But if not, just grab a measuring tape, take your time, and when ready order with confidence knowing you’ve got the right size for your ride.
Enjoy your driving, and here’s to safe, smooth amazing journeys ahead!