125/90R15 Tire Size in Inches and Millimeters

125/90R15 tires have a diameter of 23.9" (607 mm), a tread width of 4.9" (125 mm), and a wheel diameter of 15" (381 mm).The sidewall of the tire is 4.4" (113 mm), and the tire's circumference is 75" (1906 mm). This means a 125/90R15 tire will make make 845 revolutions per mile, or 525 revolutions per kilometer.

125/90R15 Tire Front
4.9"
23.9"
125/90R15 Tire Side
Tire Circumference
75"
15"
4.4"
845 Revs/Mile
SpecInchesMetric
Diameter23.9"607 mm
Width4.9"125 mm
Wheel15"381 mm
Sidewall4.4"113 mm
Circum75"1906 mm
Revolutions845 per mile525 per km

What Does 125/90R15 Mean?

The tire size 125/90R15 is a common size used on many trucks, SUVs, and other larger vehicles.

Here is what each part of the size designation represents:

  • 125: This number represents the width of the tire in millimeters. In this case, the tire is 125 millimeters wide.
  • 90: 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 90% 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.
  • 15: 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 15-inch wheel.

125/90R15 tire size meaning

How To Convert 125/90R15 Into Inches

The 125/90R15 conversion is fairly simple. The first number in the tire size, 125, represents the width of the tire in millimeters. To convert this to inches, we divide 125 by 25.4 (since there are 25.4 millimeters in an inch). This gives us approximately 4.9 inches.

The second number in the tire size, 90, represents the aspect ratio or the height of the tire as a percentage of its width. To calculate the height in inches, we multiply 4.9 by 0.90, which gives us approximately 4.4 inches.

Finally, the last number in the tire size, 15, represents the diameter of the wheel rim in inches. Therefore, the tire size 125/90R15 can be expressed in inches as roughly 4.9 inches wide, 4.4 inches tall, and designed to fit a 15-inch wheel rim.

Frequently Asked Questions About 125/90R15 Tires

How tall is a 125/90R15 tire?

A 125/90R15 tire has an approximate height, also known as the overall diameter, of 23.9 inches (607 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 125/90R15 tire?

A 125/90R15 tire has a width of approximately 4.9 inches (125 millimeters). The width of the tire is the first number in the tire size designation, which in this case is “125”. 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 125/90R15 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
125/60R1823.9"607 mm18 mm
125/70R1723.9"608 mm17 mm
125/80R1623.9"606 mm16 mm
125/85R1624.3"618 mm16 mm
125/90R1523.9"607 mm15 mm
135/60R1824.4"619 mm18 mm
135/70R1623.5"596 mm16 mm
135/70R1724.5"622 mm17 mm
135/80R1523.5"597 mm15 mm
135/80R1624.5"622 mm16 mm
135/90R1423.6"600 mm14 mm
135/90R1524.6"625 mm15 mm
155/70R1523.6"599 mm15 mm
155/80R1423.8"604 mm14 mm
165/40R1823.2"589 mm18 mm
165/65R1523.4"595 mm15 mm
165/80R1323.4"594 mm13 mm
165/80R1424.4"620 mm14 mm
175/45R1824.2"615 mm18 mm
175/55R1623.5"598 mm16 mm
175/55R1724.6"624 mm17 mm
175/60R1523.3"591 mm15 mm
175/60R1624.3"616 mm16 mm
175/65R1524"609 mm15 mm
175/70R1423.7"602 mm14 mm
175/75R1424.3"618 mm14 mm
175/80R1324"610 mm13 mm
185/50R1623.3"592 mm16 mm
185/50R1724.3"618 mm17 mm
185/55R1624"610 mm16 mm
185/60R1523.7"603 mm15 mm
185/65R1423.5"596 mm14 mm
185/65R1524.4"621 mm15 mm
185/70R1323.2"590 mm13 mm
185/70R1424.3"616 mm14 mm
195/35R1823.3"593 mm18 mm
195/45R1723.9"608 mm17 mm
195/50R1623.7"602 mm16 mm
195/55R1523.4"595 mm15 mm
195/55R1624.4"620 mm16 mm
195/60R1423.2"590 mm14 mm
195/60R1524.2"615 mm15 mm
195/65R1424"610 mm14 mm
195/70R1323.8"604 mm13 mm
205/35R1823.7"601 mm18 mm
205/40R1723.5"596 mm17 mm
205/40R1824.4"621 mm18 mm
205/45R1623.2"590 mm16 mm
205/45R1724.3"616 mm17 mm
205/50R1624.1"612 mm16 mm
205/55R1523.9"607 mm15 mm
205/60R1423.7"602 mm14 mm
205/65R1424.5"622 mm14 mm
205/70R1324.3"618 mm13 mm
215/35R1823.9"607 mm18 mm
215/40R1723.8"604 mm17 mm
215/45R1623.6"600 mm16 mm
215/50R1523.5"597 mm15 mm
215/50R1624.5"622 mm16 mm
215/55R1524.3"617 mm15 mm
215/60R1424.2"614 mm14 mm
225/30R1823.3"593 mm18 mm
225/30R1924.4"619 mm19 mm
225/35R1723.2"590 mm17 mm
225/35R1824.2"615 mm18 mm
225/40R1724.1"612 mm17 mm
225/45R1623.9"608 mm16 mm
225/50R1523.9"607 mm15 mm
225/55R1423.8"604 mm14 mm
235/30R1823.6"599 mm18 mm
235/30R1924.6"625 mm19 mm
235/35R1824.4"621 mm18 mm
235/40R1724.4"620 mm17 mm
235/45R1523.3"593 mm15 mm
235/50R1524.3"617 mm15 mm
235/60R1324.1"612 mm13 mm
245/30R1823.8"605 mm18 mm
245/35R1723.8"604 mm17 mm
245/50R1423.7"602 mm14 mm
255/30R1824.1"611 mm18 mm
255/45R1524.1"611 mm15 mm
265/30R1824.3"617 mm18 mm
265/35R1724.3"618 mm17 mm
265/50R1424.5"622 mm14 mm
275/35R1724.6"624 mm17 mm
285/40R1524"609 mm15 mm
345/35R1524.5"623 mm15 mm