Tire size in inches and millimeters

225/45R17 tire size in inches

A 225/45R17 tire is 24.97 inches tall (634.3 mm) and 8.86 inches wide (225 mm), with a 3.99-inch sidewall (101.3 mm). In inch notation that is about 25.0x8.9R17, close to a 25-inch tire (nominal).

Its circumference is 78.45 inches (1,992.7 mm), or about 808 revolutions per mile.

Nominal 225/45R17 dimensions

Overall diameter
24.97 in634.3 mm
Section width
8.86 in225 mm
Sidewall height
3.99 in101.3 mm
Circumference
78.45 in1,992.7 mm
Rim diameter
17 in
Revolutions per mile
808nominal, from geometric circumference
Inch notation
25.0x8.9R17approximate

Where 225/45R17 fits

  • Inch class: 24.97 in is within 0.1 in of a true 25 inches, so the 25-inch label is close to exact.
  • Profile: the 17-inch rim plus two 3.99 in sidewalls make up the overall diameter, and the sidewalls are 32% of it. At 45 series that is a low profile: less sidewall between the rim and the road, so the ride is usually firmer and the wheel is more exposed to potholes and curbs.
  • Same 17-inch rim: the next taller catalog size is 205/50R17 (25.07 in, +0.39%) and the next shorter is 215/45R17 (24.62 in, -1.42%).
  • Same 225 mm width: the closest in diameter are 225/50R16 (24.86 in, -0.46%), 225/40R18 (25.09 in, +0.46%), 225/55R16 (25.74 in, +3.09%), 225/50R17 (25.86 in, +3.55%). At the same width, a different profile or rim changes sidewall height and overall diameter, not section width.

Reading the marking: 225 is the section width in millimeters, 45 is the sidewall height as a percentage of that width, and R17 means radial construction for a 17-inch rim. Percentages are measured from 225/45R17.

Similar sizes on other rim diameters

Within 3% of 225/45R17's overall diameter, nearest first. The speed column is the actual speed when a speedometer calibrated for 225/45R17 reads 60 mph.

Catalog tire sizes on other rim diameters with an overall diameter close to 225/45R17
SizeOverall diameterDiameter changeAt 60 mph indicatedCompare
195/65R1524.98 in+0.03%60.02 mphComparison page for 225/45R17 vs 195/65R15
205/55R1624.88 in-0.38%59.77 mphComparison page for 225/45R17 vs 205/55R16
225/50R1624.86 in-0.46%59.73 mphNo comparison page
225/40R1825.09 in+0.46%60.27 mphComparison page for 225/45R17 vs 225/40R18
215/60R1525.16 in+0.74%60.44 mphNo comparison page
205/60R1524.69 in-1.15%59.31 mphNo comparison page

For a size without a comparison page, open 225/45R17 in the calculator and enter that size as the proposed tire.

Important: These results compare nominal dimensions. They do not confirm vehicle fitment. Actual clearance varies by tire model, approved rim width, wheel construction, suspension, alignment, body tolerances, steering angle, load, and brake geometry. Verify load and speed ratings and physically test-fit the complete setup before driving.

Physical checks before changing size

  • Approved rim-width range for the exact tire model
  • Load index and speed rating equal to or greater than vehicle requirements
  • Brake-caliper, hub, and wheel-fastener compatibility
  • Fender, liner, suspension, and full-lock steering clearance
  • Clearance at full compression and under expected load
  • Alignment, tire pressure, and manufacturer guidance
  • Professional inspection when variance or clearance is uncertain

Compare another setup

See diameter, speedometer, ride-height, and wheel-position changes.

The calculator opens with 225/45R17 as the current tire and 195/65R15, the published comparison closest in overall diameter, as the proposed tire. Change either size; wheel details stay unknown until you supply them.

Compare 225/45R17 with 195/65R15 in the calculator

Compare 225/45R17 with any size

4 of 8 keep the 17-inch rim. Diameter changes are measured from 225/45R17.

Same 17-inch rim

Larger wheels (plus sizing)

Smaller wheels

Size source and limits

Listed as a recorded tire size (source: NHTSA consumer-complaint records through May 2021, checked August 19, 2026; see methodology). A recorded size is not a safety, popularity, availability, or fitment rating.

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