255/40R13 Tire Size in Inches and Millimeters

255/40R13 tires have a diameter of 21" (534 mm), a tread width of 10" (255 mm), and a wheel diameter of 13" (330.2 mm).The sidewall of the tire is 4" (102 mm), and the tire's circumference is 65.9" (1676.8 mm). This means a 255/40R13 tire will make make 961 revolutions per mile, or 596 revolutions per kilometer.

255/40R13 Tire Front
10"
21"
255/40R13 Tire Side
Tire Circumference
65.9"
13"
4"
961 Revs/Mile
SpecInchesMetric
Diameter21"534 mm
Width10"255 mm
Wheel13"330.2 mm
Sidewall4"102 mm
Circum65.9"1676.8 mm
Revolutions961 per mile596 per km

What Does 255/40R13 Mean?

The tire size 255/40R13 is a common size used on many trucks, SUVs, and other larger vehicles.

Here is what each part of the size designation represents:

  • 255: This number represents the width of the tire in millimeters. In this case, the tire is 255 millimeters wide.
  • 40: This number represents the aspect ratio of the tire, which is the height of the tire's sidewall as a percentage of its width. In this case, the sidewall height is 40% of the tire's width.
  • R: This letter indicates the tire's construction type. “R” stands for radial construction, which is the most common type of tire construction today.
  • 13: This number represents the diameter of the wheel that the tire is designed to fit on, in inches. In this case, the tire is designed to fit on a 13-inch wheel.

255/40R13 tire size meaning

How To Convert 255/40R13 Into Inches

The 255/40R13 conversion is fairly simple. The first number in the tire size, 255, represents the width of the tire in millimeters. To convert this to inches, we divide 255 by 25.4 (since there are 25.4 millimeters in an inch). This gives us approximately 10 inches.

The second number in the tire size, 40, represents the aspect ratio or the height of the tire as a percentage of its width. To calculate the height in inches, we multiply 10 by 0.40, which gives us approximately 4 inches.

Finally, the last number in the tire size, 13, represents the diameter of the wheel rim in inches. Therefore, the tire size 255/40R13 can be expressed in inches as roughly 10 inches wide, 4 inches tall, and designed to fit a 13-inch wheel rim.

Frequently Asked Questions About 255/40R13 Tires

How tall is a 255/40R13 tire?

A 255/40R13 tire has an approximate height, also known as the overall diameter, of 21 inches (534 mm). This height can vary slightly depending on the brand and model of the tire, as well as the amount of air pressure in the tire.

How wide is a 255/40R13 tire?

A 255/40R13 tire has a width of approximately 10 inches (255 millimeters). The width of the tire is the first number in the tire size designation, which in this case is “255”. It’s important to note that the actual width of the tire may vary slightly depending on the brand and model of the tire, and the width may also be affected by the amount of air pressure in the tire.

Alternate 255/40R13 Replacement Tire Sizes

Upsizing your wheels or tires? Replacement tires must be within 3% of the diametor of the original tire. The following sizes fall within that range - click on any size to see detailed info about that tire and wheel combination.

SizeDiameterWidthWheel
105/70R1520.8"529 mm15 mm
115/70R1420.4"518 mm14 mm
115/70R1521.4"543 mm15 mm
125/70R1420.9"532 mm14 mm
125/80R1320.9"530 mm13 mm
135/70R1320.5"520 mm13 mm
135/80R1220.5"521 mm12 mm
135/80R1321.5"546 mm13 mm
145/65R1320.4"518 mm13 mm
145/65R1421.4"544 mm14 mm
145/70R1321"534 mm13 mm
145/80R1221.1"537 mm12 mm
155/55R1420.7"526 mm14 mm
155/65R1320.9"532 mm13 mm
155/70R1220.6"523 mm12 mm
155/70R1321.6"548 mm13 mm
165/40R1621.2"538 mm16 mm
165/45R1520.8"529 mm15 mm
165/50R1420.6"522 mm14 mm
165/50R1521.5"547 mm15 mm
165/55R1421.2"538 mm14 mm
165/60R1320.8"528 mm13 mm
165/65R1321.4"544 mm13 mm
165/70R1221.1"537 mm12 mm
175/50R1420.9"532 mm14 mm
175/55R1320.6"522 mm13 mm
175/60R1321.3"540 mm13 mm
185/45R1521.5"547 mm15 mm
185/50R1421.3"542 mm14 mm
185/55R1321"534 mm13 mm
195/45R1420.9"532 mm14 mm
195/55R1321.4"544 mm13 mm
205/45R1421.3"540 mm14 mm
205/50R1321.1"536 mm13 mm
215/40R1420.8"528 mm14 mm
215/50R1321.5"546 mm13 mm
225/40R1421.1"536 mm14 mm
225/45R1320.9"532 mm13 mm
255/35R1421"534 mm14 mm
255/40R1321"534 mm13 mm