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Reference

by Quadratec

Metric to Standard Conversion

Enter the metric size (i.e. 285/75 R17)

How to Use the Jeep Tire Size Calculator

  • Enter your current tire size in the calculator field.
  • Click “Convert” to see the equivalent size in standard inches.
  • Compare with recommended tire sizes for your Jeep model.
  • Use the chart below to cross-reference diameters and widths.

Also, after installing larger tires, don’t forget to check your Jeep’s gear ratio and speedometer calibration to maintain proper performance.


Whether you're upgrading to larger off-road tires or simply replacing your current set, this Jeep Tire Size Calculator helps you decode tire numbers, compare diameters, and choose the best match for your build.

Understanding Your Jeep Tire Size

Every Jeep tire is labeled with a mix of numbers and letters—but knowing what they mean is key to choosing the right replacement. For example, a 285/70R17 tire can seem confusing until you break it down:

  • 285 = Tire width in millimeters
  • 70 = Aspect ratio (the height as a percentage of width)
  • R17 = Radial tire for a 17-inch wheel

Use our free calculator to quickly convert these measurements into standard U.S. inch sizes, so you can easily compare tires and visualize how they’ll look and perform on your Jeep.

Metric to Standard Jeep Tire Conversion Made Simple

If you’re moving from stock tires to an upgraded set — especially after installing a Jeep lift kit or larger Jeep wheels, it’s essential to understand how metric sizes translate to standard ones. Our tool instantly converts common Jeep tire sizes, helping you determine:

  • Overall tire diameter (important for speedometer accuracy)
  • Sidewall height (affecting ride comfort and off-road traction)
  • Width in inches (impacting clearance and stance)

Whether you’re preparing for a set of 33-inch all-terrains for your Wrangler JL, or stepping up to 35s on your Gladiator JT, this chart provides the quick data you need.

Optimized for Jeep Owners Everywhere

From the rugged trails of Moab, Utah to the winding mountain roads of Pennsylvania, the right tire size keeps your Jeep performing at its best.

Quadratec’s Jeep Tire Size Calculator is built specifically for Jeep vehicles, helping owners across the U.S. match their tires and wheels with confidence.

shop all terrain tires
shop all terrain tires
shop all terrain tires

15-inch Wheel Conversion Chart

Metric to Standard Tire Conversion Chart for 15 inch Wheels
Metric Standard
215/75/15 27.7"x 8.5"
225/70/15 27.4"x 8.9"
225/75/15 28.3"x 8.9"
235/75/15 29.0"x 9.3"
245/75/15 29.5"x 9.6"
255/75/15 30.0"x 10.0"
265/75/15 30.6"x 10.4"

16-inch Wheel Conversion Chart

Metric to Standard Tire Conversion Chart for 16 inch Wheels
Metric Standard
205/85/16 29.7"x 8.1"
215/75/16 28.7"x 8.5"
225/70/16 28.4"x 8.9"
225/75/16 29.2"x 8.9"
235/70/16 29.0"x 9.3"
235/85/16 31.7"x 9.3"
245/70/16 29.5"x 9.6"
245/75/16 30.5"x 9.6"
255/70/16 30.0"x 10.0"
265/70/16 30.6"x 10.4"
265/75/16 31.6"x 10.4"
275/70/16 31.2"x 10.8"
285/75/16 32.8"x 11.2"
295/75/16 33.4"x 11.6"
305/70/16 33.0"x 12.2"
315/75/16 34.8"x 12.4"
375/55/16 32.8"x 15.5"
395/70/16 37.9"x 16.0"

17-inch Wheel Conversion Chart

Metric to Standard Tire Conversion Chart for 17 inch Wheels
Metric Standard
245/70/17 30.6"x 9.8
265/70/17 31.6"x 10.7
285/70/17 33.0"x 11.5
315/70/17 34.4"x 12.4

18-inch Wheel Conversion Chart

Metric to Standard Tire Conversion Chart for 18 inch Wheels
Metric Standard
275/65/18 32.1"x 11.0
375/50/18 33.0"x 15.4
325/60/18 33.2"x 13.3
325/65/18 34.8"x 13.5
305/70/18 35.0"x 12.2
375/60/18 35.7"x 15.5
395/65/18 37.8"x 15.7

20-inch Wheel Conversion Chart

Metric to Standard Tire Conversion Chart for 20 inch Wheels
Metric Standard
325/50/20 33.0"x 13.2"

Metric measurement example: 225/70R15

  1. 225 = Section width in millimeters
  2. 70 = Aspect ratio (ratio of section height to section width)
  3. R15 = Rim diameter
  4. R = Radial Construction, B = Bias Construction, D = Bias Belted Construction

Calculations for Measurements

  1. Tire Width: Section width divided by 25.4 (Ex: 225 / 25.4 = 8.86")
  2. Section Height: Tire width times aspect ratio (Ex: 8.86" x 70% = 6.20")
  3. Overall Diameter: Section height times 2 plus rim diameter (Ex: (6.20" x 2) + 15 = 27.40")

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