295/75R16 vs 305/55R20Tire Size Comparison

Safe

The 0.6% diameter difference is within the accepted 3% tolerance.

295/75R16849mm dia305/55R20844mm dia-2.7mm

Comparison Details

Overall Diameter848.9 vs 843.5 mm (-5.4 mm)
Diameter Difference-0.64%
Section Width295 vs 305 mm (+10 mm)
Sidewall Height221.3 vs 167.8 mm (-53.5 mm)
Circumference2666.9 vs 2649.9 mm
Clearance Change-2.7 mm
Speedometer Error-0.64%
Revs/Mile603 vs 607

Speedometer Correction

When switching from 295/75R16 to 305/55R20, your speedometer will differ from actual speed.

SpeedometerActual SpeedDifference
30 km/h29.8 km/h-0.2 km/h
40 km/h39.7 km/h-0.3 km/h
50 km/h49.7 km/h-0.3 km/h
60 km/h59.6 km/h-0.4 km/h
70 km/h69.6 km/h-0.4 km/h
80 km/h79.5 km/h-0.5 km/h
90 km/h89.4 km/h-0.6 km/h
100 km/h99.4 km/h-0.6 km/h
110 km/h109.3 km/h-0.7 km/h
120 km/h119.2 km/h-0.8 km/h
130 km/h129.2 km/h-0.8 km/h

Individual Tire Size Details

Practical Guidance

Switching from 295/75R16 to 305/55R20 is within the industry-accepted 3% diameter tolerance. Your speedometer, ABS, and traction control should function normally. Note: these sizes require different rim diameters (16" vs 20"), so you will need different wheels.

The 3% diameter tolerance is a widely accepted industry guideline referenced by the ETRTO and most vehicle manufacturers. When in doubt, consult your vehicle's owner's manual or a qualified tire professional. For U.S. tire safety standards and recalls, see the NHTSA Tire Safety page.

Frequently Asked Questions

Safe. The overall diameter differs by -0.64%, width changes by 10mm.

Speedometer error will be -0.64%. At an indicated 100 km/h, actual speed is about 99.4 km/h.

Ground clearance changes by -2.7mm per side.