Quick Answer
- An ATV tire size is height x width - rim diameter in inches. A 25x10-12 is nominally 25 in tall, 10 in wide, on a 12 in rim.
- Compared with 25x10-12, a 27x11-12 is 2.0 in taller: 1.00 in more ground clearance, a speedometer difference of 8.0% (an indicated 30 mph is 32.4 mph), and 807 down to 747 revs per mile (calculated).
- Published diameters run a little off nominal: Maxxis lists 25x8-12 at 25.0 to 25.6 in across its models.
New / Upgrade Tire
Format: 27×11-12 | e.g. 25×10-12
Stock / Original Tire
Format: 25×10-12
27.00"
686 mm
11.00"
279 mm
84.82"
2.155 m
747
464 / km
Rim Diameter
12"
Sidewall Height
7.500"
190.5 mm
Revs / 100 km
46414
Rolling Radius
13.500"
342.9 mm
Diameter change of 1–2 in
Diameter difference: +2.00" (+8.0%), calculated.
Polaris says to always use the size and type of tires specified for your vehicle. We have no official source for clearance or size-change limits.
Ground Clearance & Size
Speedometer Correction
Actual Speed vs Speedometer Reading
Formula: Actual Speed = (New Diameter ÷ Stock Diameter) × Displayed Speed
25×10-12
27×11-12
Get a plain-English explanation of your results and what they mean for your vehicle.
ATV Tire Size Chart: Dimensions by Size
Sidewall, circumference and revs per mile are calculated from the nominal size. Diameter, width, rim width and ply rating are the ranges published by Maxxis across its models (Maxxis 2023 US ATV/UTV catalog); other makers can differ.
| Size | Sidewall in | Circumference in | Revs per mile | Published diameter in | Published width in | Rim width in | Ply rating |
|---|---|---|---|---|---|---|---|
| 18x10-8 | 5.0 | 56.5 | 1120 | 18.5 | 10.0 | 8.0 | 4 |
| 20x11-8 | 6.0 | 62.8 | 1008 | 20.0 to 20.2 | 11.0 to 11.1 | 9.0 | 4, 6 |
| 20x11-9 | 5.5 | 62.8 | 1008 | 20.2 to 20.6 | 10.6 to 11.0 | 8.0 to 9.0 | 4, 6 |
| 20x6-10 | 5.0 | 62.8 | 1008 | 20.0 | 6.1 | 5.0 | 4 |
| 20x11-10 | 5.0 | 62.8 | 1008 | 20.0 to 20.4 | 10.8 to 10.9 | 9.0 | 4, 6 |
| 21x7-10 | 5.5 | 66.0 | 960 | 21.3 to 21.5 | 6.7 to 7.0 | 5.0 to 5.5 | 4, 6 |
| 22x10-9 | 6.5 | 69.1 | 917 | 22.0 | 9.8 | 8.0 | 6 |
| 22x11-9 | 6.5 | 69.1 | 917 | 22.2 to 22.4 | 11.0 to 11.5 | 9.0 | 6 |
| 22x7-10 | 6.0 | 69.1 | 917 | 22.2 to 22.4 | 6.7 to 6.8 | 5.5 | 6 |
| 22x11-10 | 6.0 | 69.1 | 917 | 22.0 to 22.4 | 10.8 to 11.0 | 9.0 | 4, 6 |
| 22x10-11 | 5.5 | 69.1 | 917 | 22.0 | 10.0 | 8.0 | 6 |
| 23x7-10 | 6.5 | 72.3 | 877 | 23.4 to 23.5 | 6.9 to 7.3 | 5.5 | 4, 6 |
| 23x8-12 | 5.5 | 72.3 | 877 | 23.0 | 7.5 to 8.0 | 6.5 to 7.0 | 6 |
| 23x10-12 | 5.5 | 72.3 | 877 | 23.0 to 23.3 | 9.5 to 9.7 | 8.0 | 6 |
| 24x8-11 | 6.5 | 75.4 | 840 | 24.0 | 7.8 | 6.5 | 6 |
| 24x10-11 | 6.5 | 75.4 | 840 | 24.0 | 9.8 | 8.0 | 6 |
| 24x8-12 | 6.0 | 75.4 | 840 | 24.0 | 7.8 to 7.9 | 7.0 | 6 |
| 25x11-9 | 8.0 | 78.5 | 807 | 25.0 | 10.8 | 9.0 | 6 |
| 25x11-10 | 7.5 | 78.5 | 807 | 25.0 | 11.0 | 9.0 | 6 |
| 25x8-12 | 6.5 | 78.5 | 807 | 25.0 to 25.6 | 7.6 to 8.4 | 6.0 to 7.0 | 6, 8 |
| 25x10-12 | 6.5 | 78.5 | 807 | 25.0 to 25.6 | 9.4 to 10.6 | 7.0 to 8.0 | 6, 8 |
| 25x10-14 | 5.5 | 78.5 | 807 | 25.5 | 9.8 | 8.0 | 6 |
| 26x9-12 | 7.0 | 81.7 | 776 | 26.0 to 26.6 | 8.6 to 9.0 | 7.0 | 6, 8 |
| 26x11-12 | 7.0 | 81.7 | 776 | 26.0 to 26.6 | 10.4 to 11.2 | 8.0 | 6, 8 |
| 26x12-12 | 7.0 | 81.7 | 776 | 26.4 | 11.7 | 9.5 | 6 |
| 26x8-14 | 6.0 | 81.7 | 776 | 26.0 | 7.8 | 6.0 | 6 |
| 26x9-14 | 6.0 | 81.7 | 776 | 26.2 to 26.5 | 8.5 to 9.0 | 7.0 | 6, 8 |
| 26x10-14 | 6.0 | 81.7 | 776 | 26.0 | 9.7 | 7.5 | 6 |
| 26x11-14 | 6.0 | 81.7 | 776 | 26.0 to 26.5 | 10.0 to 11.2 | 7.0 to 8.0 | 6, 8 |
| 27x9-12 | 7.5 | 84.8 | 747 | 27.0 to 27.6 | 8.4 to 9.4 | 6.0 to 7.0 | 6 |
| 27x11-12 | 7.5 | 84.8 | 747 | 27.0 to 27.6 | 10.4 to 11.3 | 7.5 to 8.0 | 6 |
| 27x12-12 | 7.5 | 84.8 | 747 | 27.7 | 11.4 to 11.7 | 9.5 | 6 |
| 27x9-14 | 6.5 | 84.8 | 747 | 27.0 to 27.4 | 8.1 to 8.7 | 6.5 to 7.0 | 6, 8 |
| 27x10-14 | 6.5 | 84.8 | 747 | 27.0 | 9.3 | 7.0 | 6 |
| 27x11-14 | 6.5 | 84.8 | 747 | 27.6 | 10.9 to 11.1 | 8.0 | 6 |
| 27x12-14 | 6.5 | 84.8 | 747 | 27.0 | 11.0 | 8.0 | 6 |
| 27x9-15 | 6.0 | 84.8 | 747 | 27.0 | 8.7 | 7.0 | 6 |
| 28x10-12 | 8.0 | 88.0 | 720 | 28.0 | 9.3 | 7.0 | 6 |
| 28x12-12 | 8.0 | 88.0 | 720 | 28.0 | 11.0 | 8.0 | 6 |
| 28x9-14 | 7.0 | 88.0 | 720 | 28.0 to 28.7 | 8.5 to 8.9 | 7.0 | 6, 8 |
| 28x10-14 | 7.0 | 88.0 | 720 | 28.0 to 28.7 | 9.3 to 10.4 | 7.0 to 8.0 | 8 |
| 28x11-14 | 7.0 | 88.0 | 720 | 28.3 to 29.2 | 10.4 to 10.6 | 8.0 | 6, 8 |
| 28x9-15 | 6.5 | 88.0 | 720 | 28.2 | 8.3 | 6.5 | 6 |
| 28x11-15 | 6.5 | 88.0 | 720 | 28.5 | 10.7 | 8.0 | 6 |
| 29x9-14 | 7.5 | 91.1 | 695 | 28.7 to 29.5 | 8.7 to 9.1 | 6.0 to 7.0 | 6 |
| 29x11-14 | 7.5 | 91.1 | 695 | 29.4 to 29.5 | 10.6 to 11.1 | 8.0 | 6, 8 |
| 29x9.5-15 | 7.0 | 91.1 | 695 | 29.7 | 9.3 to 9.4 | 7.0 | 8 |
| 29x9.5-16 | 6.5 | 91.1 | 695 | 30.0 | 9.3 | 7.0 | 8 |
| 30x9-14 | 8.0 | 94.2 | 672 | 30.0 to 30.2 | 8.7 to 9.1 | 7.0 | 6, 8 |
| 30x10-14 | 8.0 | 94.2 | 672 | 30.4 to 31.1 | 9.7 to 10.6 | 7.0 to 8.0 | 6, 8 |
| 30x11-14 | 8.0 | 94.2 | 672 | 30.0 | 10.5 to 11.2 | 7.0 to 8.0 | 6, 8 |
| 30x10-15 | 7.5 | 94.2 | 672 | 30.8 | 9.6 | 7.0 | 8 |
| 31x10-15 | 8.0 | 97.4 | 651 | 31.6 | 10.0 | 8.0 | 8 |
| 32x10-14 | 9.0 | 100.5 | 630 | 32.0 to 32.3 | 10.0 to 10.6 | 7.0 | 8 |
| 32x10-15 | 8.5 | 100.5 | 630 | 32.0 to 32.7 | 10.0 to 10.6 | 7.0 | 8 |
| 33x10-15 | 9.0 | 103.7 | 611 | 33.5 to 33.7 | 10.2 | 7.0 | 8 |
| 35x10-14 | 10.5 | 110.0 | 576 | 34.7 | 11.0 | 7.0 | 8 |
| 35x10-15 | 10.0 | 110.0 | 576 | 35.4 to 35.5 | 10.4 to 10.6 | 7.0 | 8 |
| 35x10-17 | 9.0 | 110.0 | 576 | 35.4 | 10.2 | 7.0 | 8 |
| 37x10-17 | 10.0 | 116.2 | 545 | 37.2 to 37.3 | 10.5 to 10.8 | 7.0 | 8 |
ATV Tire Size Change Examples
Calculated from the nominal sizes. These are not fitment approvals: check clearance and rim size with your ATV maker.
| Stock size | New size | Diameter change | Clearance change | Speedometer error | True speed at 30 mph |
|---|---|---|---|---|---|
| 25x8-12 | 26x8-12 | +1.0 in | +0.50 in | +4.0% | 31.2 mph |
| 25x10-12 | 26x10-12 | +1.0 in | +0.50 in | +4.0% | 31.2 mph |
| 25x10-12 | 27x10-12 | +2.0 in | +1.00 in | +8.0% | 32.4 mph |
| 26x10-12 | 28x10-12 | +2.0 in | +1.00 in | +7.7% | 32.3 mph |
| 25x10-12 | 28x10-12 | +3.0 in | +1.50 in | +12.0% | 33.6 mph |
| 27x11-12 | 29x11-14 | +2.0 in | +1.00 in | +7.4% | 32.2 mph |
| 28x10-14 | 30x10-14 | +2.0 in | +1.00 in | +7.1% | 32.1 mph |
Metric ATV Tire Sizes in Inches
Some ATV tires carry a car-style marking. Diameter = rim + 2 x width x aspect / 100 / 25.4. Calculated, and the sizes shown are examples.
| Metric size | Diameter in | Width in | Rim in |
|---|---|---|---|
| 205/80R12 | 24.9 | 8.1 | 12 |
| 205/80R13 | 25.9 | 8.1 | 13 |
| 195/80R12 | 24.3 | 7.7 | 12 |
| 225/75R12 | 25.3 | 8.9 | 12 |
For other formats use the flotation size converter and the metric tire calculator.
ATV Tire Formulas and Manufacturer Statements
Sidewall height
(overall diameter - rim) / 2. For 25x10-12: (25 - 12) / 2 = 6.5 in.
Circumference and revs per mile
Circumference = pi x diameter = 78.5 in for 25 in. Revs per mile = 63,360 / circumference = 807.
Ground clearance change
Half the diameter difference, because the axle rises by the change in radius. Going from 25 to 27 in adds 1 in.
Speedometer error
The percentage diameter change: (new - stock) / stock x 100. Actual speed = indicated speed x new diameter / stock diameter.
| Source | Statement (paraphrased) |
|---|---|
| Maxxis, 2023 ATV/UTV catalog (safety page) | Consult the owner's manual for tire information. Check with the ATV maker before mounting sizes that differ from those in the manual, because altering the tire size may require a different rim size, and keep adequate clearance around the tires at all times. |
| Maxxis, 2023 ATV/UTV catalog (size tables) | Each model's table lists overall diameter, overall width, rim size, tire pressure, max load and ply rating for every size. The chart on this page summarizes those values by nominal size. |
| Polaris, 2025 Sportsman 570 owner's manual | Always use the size and type of tires specified for the vehicle. The manual lists 25x8-12 front and 25x10-12 rear, and warns that non-approved modifications, including tires, may change handling. |
Reading sizes and where to find pressure are covered in the ATV tire size guide; UTV sizes are in the UTV tire guide.
How to Use the ATV Tire Size Calculator
- 1Pick Compare vs Stock, or Single Tire to decode one size.
- 2Enter the new size as height x width - rim, for example 27x11-12.
- 3Enter your stock size in the same format, for example 25x10-12.
- 4Read the diameter, sidewall, revs per mile, ground clearance change and speedometer error. Results update as you type.
- 5Check the true speed table for what your speedometer shows against actual speed.