215/60R16 vs 245/40R18 Tire Comparison

215/60R16 has nominal diameter 26.1575 in; 245/40R18 has 25.7165 in. Diameter changes -1.686%; at indicated 60 mph the new nominal speed is 58.989 mph. Selected standard passenger and common truck/SUV tire sizes, not a verified market-popularity ranking. Nominal dimensions do not guarantee vehicle fitment.

215/60R16 vs 245/40R18 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

215/60R16 has nominal diameter 26.1575 in; 245/40R18 has 25.7165 in. Diameter changes -1.686%; at indicated 60 mph the new nominal speed is 58.989 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 215/60R16 vs 245/40R18 Tire Comparison

  1. Check Tire width (mm): 215.
  2. Check Tire aspect ratio (%): 60.
  3. Check Tire rim diameter (inches): 16.
  4. Check Tire B width (mm): 245.
  5. Check Tire B aspect ratio (%): 40.
  6. Check Tire B rim diameter (inches): 18.
  7. Check Indicated speed (mph): 60.
  8. Review the 215/60R16 vs 245/40R18 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

215/60R16 vs 245/40R18 Tire Comparison: Tire width (mm) = 215; Tire aspect ratio (%) = 60; Tire rim diameter (inches) = 16; Tire B width (mm) = 245; Tire B aspect ratio (%) = 40; Tire B rim diameter (inches) = 18; Indicated speed (mph) = 60. 215/60R16 has nominal diameter 26.1575 in; 245/40R18 has 25.7165 in. Diameter changes -1.686%; at indicated 60 mph the new nominal speed is 58.989 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)215
  • Tire aspect ratio (%)60
  • Tire rim diameter (inches)16
  • Tire B width (mm)245
  • Tire B aspect ratio (%)40
  • Tire B rim diameter (inches)18
  • Indicated speed (mph)60

Result

  • Diameter difference (%)-1.69
  • Actual speed (mph)58.99
  • Ground clearance change-0.22 in

215/60R16 versus 245/40R18

MeasurementOriginal tireNew tire
Diameter (in)26.1574803149606325.716535433070867
Sidewall (in)5.0787401574803153.8582677165354333
Circumference (in)82.1761479938999580.79087879231705
Revolutions/mile771.0266488118098784.2469465256681
Speed at indicated 30 mph3029.494280553883204
Speed at indicated 45 mph4544.2414208308248
Speed at indicated 60 mph6058.98856110776641
Speed at indicated 70 mph7068.81998795906081

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 -0.4409 inches (-1.686%).

5.0787 and 3.8583 inches respectively.

Nominal actual speed becomes 58.989 mph if calibrated to 215/60R16.

771.03 versus 784.25 geometric revolutions/mile.

This comparison cannot confirm fitment. Ground clearance changes -0.2204724409448815 in geometrically; verify wheel width, offsets, load/speed ratings and manufacturer requirements.