255/25R21 in Inches
Understanding the dimensions of the 255/25R21 tire size in both metric and imperial units of measurement is an essential part of tire maintenance and replacement. Let us take a closer look at every important aspect of the 255/25R21 tire to understand what these numbers represent and how they may affect your vehicle's performance.
- What is 255/25R21 in inches?
- How to convert 255/25R21 to inches?
- How to read 255/25R21 tire size?
- Where to buy new 255/25R21 tires?
- How wide is a 255/25R21 tire?
- How tall is a 255/25R21 tire?
- 255/25R21 tire sidewall height
- What size rim fits a 255/25R21 tire?
- 255/25R21 tire circumference
- How many revolutions does a 255/25R21 tire make?
What is 255/25R21 in inches?
When we convert 255/25R21 to inches, it is equivalent to 26x10R21 tire size in the high flotation system. 255/25R21 tires have a diameter of 26" (661 mm), a tread width of 10" (255 mm), and can be mounted on a wheel with a diameter of 21" (533 mm). The sidewall of the tire is 2.5" (64 mm), and the tire's circumference is 81.6" (2076 mm). This means a 255/25R21 tire will make 776 revolutions per mile, or 482 revolutions per kilometer.



Metric | Inches | |
---|---|---|
Tire Diameter | 661 mm | 26" |
Tread Width | 255 mm | 10" |
Aspect Ratio | 25% | |
Rim Diameter | 533 mm | 21" |
Sidewall Height | 64 mm | 2.5" |
Circumference | 2076 mm | 81.6" |
Revolutions | 482 per km | 776 per mile |
How to read 255/25R21 tire size?
Reading a tire size such as can be broken down into three main parts: tread width, aspect ratio and rim diameter.
255 is the width of the tire in millimeters from sidewall to sidewall when it's fully inflated and not under any load. In this example, the tire is 255 millimeters wide.
25 represents the height of the tire's cross-section as a percentage of its width. It means the height is 25% of the tire's width.
R denotes that tire has radial construction.
21 is the diameter of the wheel that the tire fits on, measured in inches. This tire would fit on a 21-inch wheel.
How to convert 255/25R21 to inches
The 255/25R21 conversion is very simple. There are 25.4 millimeters in an inch. All we have to do is divide tread width and sidewall height by 25.4 to convert to inches.
To convert the tire width to inches, you divide 255 mm by 25.4, yielding a tire width of approximately 10 inches. To find the sidewall height in inches, you calculate 25% of the tire width in millimeters (255 mm), convert this figure to inches as before, resulting in a sidewall height of about 2.5 inches. However, to understand the tire's overall diameter, you need to consider the height of two sidewalls and the diameter of the wheel it fits. Therefore, you multiply the sidewall height by 2 and add the wheel diameter (21 inches), giving you an overall tire diameter of approximately 26 inches.
So, when converted to inches, 255/25R21 tire is 10 inches wide, 26 inches tall, and fits 21-inch rims.
How wide is a 255/25R21 tire?
Tire width, also known as section width, is a measurement in millimeters that indicates the width of a tire from one sidewall to the other. It is the first number provided in a tire's size specifications. 255/25R21 tire has a width of 10 inches or 255 mm.
A greater tire width can increase the tire's contact patch with the road, potentially improving grip and handling. However, wider tires can also increase rolling resistance, which could negatively impact fuel efficiency.

How tall is a 255/25R21 tire?
Tire height, also known as the tire's diameter or overall diameter, is the measurement from the ground to the top of the tire. It's essentially the distance from one side of the tire to the other, passing through the center, when it's correctly inflated and not under load. 255/25R21 tire has a diameter or height of 26 inches or 661 mm.

255/25R21 Tire Sidewall Height
Tire sidewall height, also known as the tire's aspect ratio, is the measurement of the height of the tire's cross-section or the height of the tire from the rim to the tread. It is typically represented as a percentage of the tire's width. 255/25R21 tire has a sidewall height of 2.5 inches or 64 mm.
Sidewall height (also known as tire profile) can greatly affect a tire's driving characteristics. Lower profile tires (30 or 35 series) often provide better handling but can give a harsher ride, while higher profile tires (65 or 70 series) generally provide a smoother ride but with less precise handling.

What size rim fits a 255/25R21 tire?
The rim diameter refers to the diameter of the wheel on which a tire is mounted. It is the distance from one edge of the rim to the opposite edge, passing through the center of the wheel. 255/25R21 tire can be mounted on 21-inch wheels.
The rim diameter is crucial not only for fitting the tire properly but also plays a role in determining the overall performance of the vehicle, including its handling and ride quality.

255/25R21 Tire Circumference
Tire circumference refers to the distance around the outer edge of a tire. It is the measurement of the entire circumference or perimeter of the tire when it is inflated and mounted on a wheel. 255/25R21 tire has a circumference of 81.6 inches or 2076 mm.

How many revolutions does a 255/25R21 tire make?
Tire revolutions refer to the number of complete rotations a tire makes while the vehicle is in motion. It is a measure of the distance covered by the tire. 255/25R21 tire completes 776 revolutions per mile or 482 revolutions per kilometer.
Tire revolutions are often used in various calculations related to vehicle dynamics, such as determining the distance traveled, estimating fuel consumption, or calculating the speed of the vehicle based on the rotation of the tires. Tire revolutions can also be tracked or monitored by certain vehicle systems, such as the anti-lock braking system (ABS) or the vehicle's onboard computer, for various purposes.

More 21-inch Tire Conversions
- 225/45R21 = 28.9x8.9R21
- 235/50R21 = 30.3x9.3R21
- 245/35R21 = 27.8x9.6R21
- 245/40R21 = 28.7x9.6R21
- 245/45R21 = 29.6x9.6R21
- 255/35R21 = 28x10R21
- 255/40R21 = 29x10R21
- 255/50R21 = 31.1x10R21
- 265/35R21 = 28.3x10.4R21
- 265/40R21 = 29.3x10.4R21
- 265/45R21 = 30.4x10.4R21
- 275/30R21 = 27.5x10.8R21
- 275/35R21 = 28.5x10.8R21
- 275/40R21 = 29.6x10.8R21
- 275/45R21 = 30.7x10.8R21
- 275/50R21 = 31.9x10.8R21
- 275/55R21 = 32.9x10.8R21
- 285/35R21 = 28.9x11.2R21
- 285/40R21 = 30x11.2R21
- 285/45R21 = 31.1x11.2R21
- 295/35R21 = 29.1x11.6R21
- 295/40R21 = 30.3x11.6R21
- HL245/35R21 = 27.8x9.6R21
- HL255/35R21 = 28x10R21
- P265/45R21 = 30.4x10.4R21
- 285/30R21 = 27.8x11.2R21
- 295/30R21 = 28x11.6R21
- 305/30R21 = 28.2x12R21
- 305/35R21 = 29.4x12R21
- 315/30R21 = 28.5x12.4R21
- 315/35R21 = 29.6x12.4R21
- 315/40R21 = 30.9x12.4R21
- 315/45R21 = 32.2x12.4R21
- 325/30R21 = 28.7x12.8R21
- 325/40R21 = 31.2x12.8R21
- 335/30R21 = 28.9x13.2R21
- 345/25R21 = 27.8x13.6R21
- 355/25R21 = 28x14R21
- HL265/35R21 = 28.3x10.4R21
- HL285/30R21 = 27.8x11.2R21
- 235/30R21 = 26.6x9.3R21
- 235/35R21 = 27.4x9.3R21
- 235/45R21 = 29.3x9.3R21
- 245/25R21 = 25.8x9.6R21
- 245/30R21 = 26.8x9.6R21
- 255/25R21 = 26x10R21
- 255/30R21 = 27x10R21
- 255/45R21 = 30x10R21
- 265/30R21 = 27.3x10.4R21
- 275/25R21 = 26.4x10.8R21
- 295/25R21 = 26.8x11.6R21
- 305/25R21 = 27x12R21
- 305/40R21 = 30.6x12R21
- 325/25R21 = 27.4x12.8R21
- 345/30R21 = 29.2x13.6R21
- 375/35R21 = 31.3x14.8R21
- HL255/40R21 = 29x10R21
- HL285/35R21 = 28.9x11.2R21
- P245/45R21 = 29.6x9.6R21
- P265/35R21 = 28.3x10.4R21
- P275/30R21 = 27.5x10.8R21
- P295/35R21 = 29.1x11.6R21
- P295/40R21 = 30.3x11.6R21
- P255/45R21 = 30x10R21
- P245/35R21 = 27.8x9.6R21
- P275/50R21 = 31.9x10.8R21
- P295/25R21 = 26.8x11.6R21
- 375/20R21 = 26.9x14.8R21
- P315/35R21 = 29.6x12.4R21
- HL295/30R21 = 28x11.6R21
- HL295/35R21 = 29.1x11.6R21
- HL305/30R21 = 28.2x12R21
All listed guides, data and/or calculations are for informational purposes only. TireConverter.com does not warrant or make any representations regarding the accuracy of or the results of the use of this information.