285/50R22 vs 305/45R22

285/50R22 is 0.4" taller than 305/45R22 (1.2%)

Diameter difference−1.24%diameter 33.22" → 32.81"
285/50R22305/45R22
285/50R22305/45R22Difference
Overall diameter33.22"32.81"−0.41"
Section width11.22"12.01"+0.79"
Sidewall height5.61"5.40"−0.21"
Circumference104.4"103.1"−1.3"
Revolutions per mile607615+8
Wheel diameter22"22"±0"

Speedometer

ShowsActualDiff
30 mph29.6 mph−0.4
45 mph44.4 mph−0.6
60 mph59.3 mph−0.7
70 mph69.1 mph−0.9
80 mph79.0 mph−1.0

Gear ratio to match

CurrentEquivalent
3.423.38
3.553.51
3.733.68
4.104.05

305/45R22 is 0.41" shorter than 285/50R22, a −1.24% change in diameter, inside the 3% range most shops treat as a safe swap.

Ground clearance changes by 0.21" (half the diameter change), and the tire needs 0.21" less room above it.

305/45R22 is 0.79" wider. On the same wheel offset about half of that, 0.39", moves toward the suspension and half toward the fender.

Both fit a 22" wheel; the sidewall is 0.21" shorter on 305/45R22.

Details: 285/50R22 in inches · 305/45R22 in inches · change sizes in the calculator

FAQ

What is the difference between 285/50R22 and 305/45R22?

305/45R22 is 0.41" shorter (−1.24%) and 0.79" wider than 285/50R22.

Will 305/45R22 change my speedometer?

Yes, by −1.24%. When the speedometer shows 60 mph you would be going 59.3 mph.

Can I replace 285/50R22 with 305/45R22?

Often yes: the diameter change of −1.2% is within the common 3% guideline. Check the load index, speed rating and clearance.