How tall is a 245/45R18 tire?

A 245/45R18 has a nominal overall diameter of 26.68 inches (678 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 245/45R18 tire fit?

A 245/45R18 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 245/45R18 mean?

245 is the section width in millimetres. 45 is the aspect ratio — the sidewall is 45% of the width, so 110.3 mm here. R marks the construction (radial). 18 is the wheel diameter in inches.

Free shipping on select tires

Brand-new, never-mounted tires

Ships to your door or installer

Thousands of tires in stock

Free shipping on select tires

Brand-new, never-mounted tires

Ships to your door or installer

Thousands of tires in stock

Size Dimensions & Specs

Tires Size 245/45R18

Dimensions, specs, and every size 245/45R18 tire currently in stock

Overall Height

26.68"

678 mm · calculated

Section Width

245 mm

9.65 inches

Sidewall Height

4.34"

110.3 mm · 45% profile

Wheel Diameter

18"

457.2 mm

245/45R18 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	45%	—
Sidewall height	4.34 in	110.3 mm
Overall diameter (calculated)	26.68 in	678 mm
Wheel / rim diameter	18 in	457.2 mm
Construction	Radial	—

What does 245/45R18 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

45% profile

The sidewall stands 45% of the section width, which is 110.3 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.

245/45R18 Questions & Answers

Dimensions and fitment guidelines for size 245/45R18

Customer Support & Fitment Advice

Need Help Choosing The Right Tires?

Have questions about fitment, brands, or pricing? Our team of tire experts is here to guide you to the perfect set — zero pressure, zero sales tactics.

Free Fitment Advice

Talk to a Tire Specialist Today

We make tire buying fast and effortless. Call or email us (Mon – Sat, 9AM – 5PM PT) to check size compatibility, load index, or speed ratings for your vehicle.

Call Direct

(916) 520-1702

Send Email

info@natireshub.com

Mon – Sat, 9AM – 5PM PT

✓

Expert Advice

Reply within 1 business day

Live Inventory

Shop Our Collection

Explore premium tires, wheels, and fitments from top brands

Tires Size 245/45R18

Filter & search

Filter & search

245/45R18 Specifications

What does 245/45R18 mean?

245 mm

45% profile

Radial

18 in

245/45R18 Questions & Answers

Need Help Choosing The Right Tires?

Talk to a Tire Specialist Today

Shop Our Collection