How tall is a P245/70R18 tire?

A P245/70R18 has a nominal overall diameter of 31.5 inches (800 mm), calculated as the 18-inch wheel plus two sidewalls. This is the unloaded figure — a fitted tire sits fractionally shorter under the weight of the vehicle.

What wheel size does a P245/70R18 tire fit?

A P245/70R18 fits a wheel of 18 inches in diameter. The wheel also has to be within the rim width range the manufacturer publishes for this size, which is printed in the tire's spec sheet.

What do the numbers in P245/70R18 mean?

245 is the section width in millimetres. 70 is the aspect ratio — the sidewall is 70% of the width, so 171.5 mm here. R marks the construction (radial). 18 is the wheel diameter in inches.

Size Dimensions & Specs

Tires Size P245/70R18

Dimensions, specs, and every size P245/70R18 tire currently in stock

Overall Height

31.5"

800 mm · calculated

Section Width

245 mm

9.65 inches

Sidewall Height

6.75"

171.5 mm · 70% profile

Wheel Diameter

18"

457.2 mm

P245/70R18 Specifications

Read directly from the size code. Load index, speed rating, and rim width range vary by model.

Specification	Imperial	Metric
Section width	9.65 in	245 mm
Aspect ratio	70%	—
Sidewall height	6.75 in	171.5 mm
Overall diameter (calculated)	31.5 in	800 mm
Wheel / rim diameter	18 in	457.2 mm
Construction	Radial	—
Service type	Passenger car	—

What does P245/70R18 mean?

Reading the code on your sidewall

Section width

245 mm

The distance from sidewall to sidewall across the tire's widest point.

Aspect ratio

70% profile

The sidewall stands 70% of the section width, which is 171.5 mm on this size.

Construction (R)

Radial

The body plies run across the tire at right angles to the direction of travel.

Wheel diameter

18 in

Fits a wheel measuring 18 inches across.

P245/70R18 Questions & Answers

Dimensions and fitment guidelines for size P245/70R18

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