215/55R17 vs 285/70R17 Tire Comparison

215/55R17 has nominal diameter 26.3110 in; 285/70R17 has 32.7087 in. Diameter changes 24.315%; at indicated 60 mph the new nominal speed is 74.589 mph. Selected standard passenger and common truck/SUV tire sizes, not a verified market-popularity ranking. Nominal dimensions do not guarantee vehicle fitment.

215/55R17 vs 285/70R17 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

215/55R17 has nominal diameter 26.3110 in; 285/70R17 has 32.7087 in. Diameter changes 24.315%; at indicated 60 mph the new nominal speed is 74.589 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 215/55R17 vs 285/70R17 Tire Comparison

  1. Check Tire width (mm): 215.
  2. Check Tire aspect ratio (%): 55.
  3. Check Tire rim diameter (inches): 17.
  4. Check Tire B width (mm): 285.
  5. Check Tire B aspect ratio (%): 70.
  6. Check Tire B rim diameter (inches): 17.
  7. Check Indicated speed (mph): 60.
  8. Review the 215/55R17 vs 285/70R17 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

215/55R17 vs 285/70R17 Tire Comparison: Tire width (mm) = 215; Tire aspect ratio (%) = 55; Tire rim diameter (inches) = 17; Tire B width (mm) = 285; Tire B aspect ratio (%) = 70; Tire B rim diameter (inches) = 17; Indicated speed (mph) = 60. 215/55R17 has nominal diameter 26.3110 in; 285/70R17 has 32.7087 in. Diameter changes 24.315%; at indicated 60 mph the new nominal speed is 74.589 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 (%)55
  • Tire rim diameter (inches)17
  • Tire B width (mm)285
  • Tire B aspect ratio (%)70
  • Tire B rim diameter (inches)17
  • Indicated speed (mph)60

Result

  • Diameter difference (%)24.32
  • Actual speed (mph)74.59
  • Ground clearance change3.2 in

215/55R17 versus 285/70R17

MeasurementOriginal tireNew tire
Diameter (in)26.31102362204724432.70866141732284
Sidewall (in)4.6555118110236227.854330708661418
Circumference (in)82.65851851945114102.75729041741734
Revolutions/mile766.527166647563616.5985862669311
Speed at indicated 30 mph3037.29462816100554
Speed at indicated 45 mph4555.94194224150831
Speed at indicated 60 mph6074.58925632201108
Speed at indicated 70 mph7087.02079904234625

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 6.3976 inches (24.315%).

4.6555 and 7.8543 inches respectively.

Nominal actual speed becomes 74.589 mph if calibrated to 215/55R17.

766.53 versus 616.60 geometric revolutions/mile.

This comparison cannot confirm fitment. Ground clearance changes 3.1988188976377963 in geometrically; verify wheel width, offsets, load/speed ratings and manufacturer requirements.