285/55R20 Tire Size: 32.3" Tall, a 32-Inch Tire
Straight answer
A 285/55R20 stands 32.3 inches tall and 11.2 inches wide on a 20-inch wheel, which makes it a 32-inch tire in truck-speak. NTW stocks 22 tire models in this size right now.
285/55R20 dimensions
Overall diameter
32.34"
Section width
11.22"
Sidewall height
6.17"
Wheel diameter
20"
Circumference
101.6"
Revolutions per mile
624
≈ 32.3x11.2R20 flotation. Nominal math; real tires run a few tenths off depending on brand, load range, rim width, and air pressure.
What 285/55R20 means
- 285Section width: 285 mm (11.2") wall to wall
- 55Aspect ratio: sidewall is 55% of the width, so 6.2" tall
- RRadial construction
- 20Fits a 20-inch wheel
Want the full rundown on sidewall codes, load index, and speed rating? Read how to read a tire size.
285/55R20 compared to nearby 20-inch sizes
Speedometer column assumes your truck is calibrated for 285/55R20 and reads 65 mph.
| Size | Height | vs 285/55R20 | Width change | Actual speed | Compare |
|---|---|---|---|---|---|
| 275/55R20 | 31.9" | -0.4" (-1.3%) | -0.4" | 64.1 mph | Full comparison |
| 275/60R20 | 33.0" | +0.6" (+2.0%) | -0.4" | 66.3 mph | Full comparison |
| 33x12.50R20 | 33.0" | +0.7" (+2.0%) | +1.3" | 66.3 mph | Full comparison |
| 305/55R20 | 33.2" | +0.9" (+2.7%) | +0.8" | 66.7 mph | Full comparison |
| 295/60R20 | 33.9" | +1.6" (+4.9%) | +0.4" | 68.2 mph | Full comparison |
Rule of thumb: inside 3% of stock diameter feels stock; past 8 to 10% and most owners budget for a re-gear. Run your exact numbers in the tire size calculator, or check what stepping down to 275/55R20 does.
Tires in stock in 285/55R20
22 models, 27 SKUs at NTW (different load ranges and sidewall styles). Refreshed daily.
| Tire | Type | Options | From |
|---|---|---|---|
| Falken Wildpeak A/T4W | All Terrain | 2 | $400 |
| Nitto Recon Grappler A/T | All Terrain | 2 | $336 |
| Nitto Terra Grappler G3 | All Terrain | 2 | $318 |
| Toyo Open Country A/T III | All Terrain | 2 | $336 |
| Toyo Open Country R/T Trail | All Terrain | 2 | $346 |
| AMP Off-Road AT Terrain Attack | All Terrain | 1 | $266 |
| AMP Off-Road Mud Terrain Attack MT | Mud Terrain | 1 | $311 |
| AMP Off-Road Terrain Attack R/T | All Terrain | 1 | $306 |
| AMP Off-Road Terrain Pro AT | All Terrain | 1 | $256 |
| Avix Off-Road TRAILTEK R/T | All Terrain, Mud Terrain, On/Off-Road | 1 | $307 |
| Bfgoodrich All-Terrain T/A KO3 | All Terrain | 1 | $445 |
| Falken Rubitrek A/T | All Terrain | 1 | $398 |
| Falken Wildpeak R/T01 | All Terrain | 1 | $506 |
| Kenda Klever RT | All Terrain | 1 | $356 |
| Mickey Thompson Baja Boss | Mud Terrain | 1 | $460 |
| Mickey Thompson Baja Boss AT | All Terrain | 1 | $467 |
| Mickey Thompson Baja Legend EXP | All Terrain | 1 | $417 |
| Nitto Ridge Grappler | All Terrain | 1 | $456 |
| Nitto Trail Grappler M/T | Mud Terrain | 1 | $480 |
| Toyo Open Country C/T | All Terrain | 1 | $460 |
| Toyo Open Country R/T | All Terrain | 1 | $467 |
| Venom Power Terra Hunter RT Plus | All Terrain | 1 | $282 |
Prices per tire at NTW when last checked; confirm at checkout.
Frequently Asked Questions
How tall is a 285/55R20 tire in inches?+
A 285/55R20 is 32.34 inches tall and 11.22 inches wide, with a 6.17-inch sidewall on a 20-inch wheel. Real mounted tires vary a few tenths of an inch by brand, load range, and rim width.
Is 285/55R20 a 32-inch tire?+
Close enough that everybody calls it one. It measures 32.3 inches, so it's sold and talked about as a 32. The flotation equivalent is 32.3x11.2R20.
What does 285/55R20 mean?+
285/55R20 means a tire 285 millimeters wide with a sidewall 55% as tall as it is wide, built for a 20-inch wheel.
285/55R20 vs 275/60R20: how much bigger?+
275/60R20 is 0.6 inches taller (2.0%) and 0.4 inches narrower. Going from 285/55R20 to 275/60R20, a speedometer reading 65 mph means you're actually doing 66.3.
Looking for another size? See the full truck tire size chart.