245/45R18 vs 265/75R16 Tire Comparison

245/45R18 has nominal diameter 26.6811 in; 265/75R16 has 31.6496 in. Diameter changes 18.622%; at indicated 60 mph the new nominal speed is 71.173 mph. Selected standard passenger and common truck/SUV tire sizes, not a verified market-popularity ranking. Nominal dimensions do not guarantee vehicle fitment.

245/45R18 vs 265/75R16 Tire Comparison reference last updated · reference source

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Dated static reference; no live data is fetched. Verify current source values and assumptions before relying on results.

What this tool does

245/45R18 has nominal diameter 26.6811 in; 265/75R16 has 31.6496 in. Diameter changes 18.622%; at indicated 60 mph the new nominal speed is 71.173 mph. Selected standard passenger and common truck/SUV tire sizes, not a verified market-popularity ranking. Nominal dimensions do not guarantee vehicle fitment.

How to use the 245/45R18 vs 265/75R16 Tire Comparison

  1. Check Tire width (mm): 245.
  2. Check Tire aspect ratio (%): 45.
  3. Check Tire rim diameter (inches): 18.
  4. Check Tire B width (mm): 265.
  5. Check Tire B aspect ratio (%): 75.
  6. Check Tire B rim diameter (inches): 16.
  7. Check Indicated speed (mph): 60.
  8. Review the 245/45R18 vs 265/75R16 Tire Comparison result and its exact-value comparison table.
  9. Verify assumptions before applying the result.

Formula

difference%=(diameterB/diameterA−1)×100; actual speed=indicated speed×diameterB/diameterA
width
Tire width (mm)
aspect
Tire aspect ratio (%)
rim
Tire rim diameter (inches)
widthB
Tire B width (mm)
aspectB
Tire B aspect ratio (%)
rimB
Tire B rim diameter (inches)
speed
Indicated speed (mph)

Assumes the speedometer was calibrated to the original tire. Does not check wheel offset, width or clearance.

Worked example

245/45R18 vs 265/75R16 Tire Comparison: Tire width (mm) = 245; Tire aspect ratio (%) = 45; Tire rim diameter (inches) = 18; Tire B width (mm) = 265; Tire B aspect ratio (%) = 75; Tire B rim diameter (inches) = 16; Indicated speed (mph) = 60. 245/45R18 has nominal diameter 26.6811 in; 265/75R16 has 31.6496 in. Diameter changes 18.622%; at indicated 60 mph the new nominal speed is 71.173 mph. Selected standard passenger and common truck/SUV tire sizes, not a verified market-popularity ranking. Nominal dimensions do not guarantee vehicle fitment.

Inputs

  • Tire width (mm)245
  • Tire aspect ratio (%)45
  • Tire rim diameter (inches)18
  • Tire B width (mm)265
  • Tire B aspect ratio (%)75
  • Tire B rim diameter (inches)16
  • Indicated speed (mph)60

Result

  • Diameter difference (%)18.62
  • Actual speed (mph)71.17
  • Ground clearance change2.48 in

245/45R18 versus 265/75R16

MeasurementOriginal tireNew tire
Diameter (in)26.68110236220472631.6496062992126
Sidewall (in)4.3405511811023627.8248031496063
Circumference (in)83.8211551707796599.43017063861555
Revolutions/mile755.8950943936348637.2311300790725
Speed at indicated 30 mph3035.58654271801682
Speed at indicated 45 mph4553.37981407702523
Speed at indicated 60 mph6071.17308543603365
Speed at indicated 70 mph7083.03526634203924

Results explained

Diameter difference (%)
Diameter difference (%) from the formula above. Assumes the speedometer was calibrated to the original tire. Does not check wheel offset, width or clearance.
Actual speed (mph)
Actual speed (mph) from the formula above. Assumes the speedometer was calibrated to the original tire. Does not check wheel offset, width or clearance.
Ground clearance change
Ground clearance change from the formula above, expressed in in before metric conversion. Assumes the speedometer was calibrated to the original tire. Does not check wheel offset, width or clearance.

Frequently asked questions

Diameter difference is 4.9685 inches (18.622%).

4.3406 and 7.8248 inches respectively.

Nominal actual speed becomes 71.173 mph if calibrated to 245/45R18.

755.90 versus 637.23 geometric revolutions/mile.

This comparison cannot confirm fitment. Ground clearance changes 2.484251968503937 in geometrically; verify wheel width, offsets, load/speed ratings and manufacturer requirements.