CarSpecsHQ

295/30R18 vs 225/45R17

225/45R17 is a safe swap for 295/30R18 by the usual ±3% rule: the diameter differs by +0.02%.

18" → 17"
295/30R18 24.97" · 225/45R17 24.97" · drawn to scale

Side by side

295/30R18225/45R17Difference
Overall diameter24.97"24.97"+0.00" (+0.02%)
Section width295 mm225 mm-70 mm
Sidewall3.48"3.99"+0.50"
Rim18"17"-1"
Circumference78.4"78.5"+0.0"
Revs per mile808808-0
Ride height——+0.00"
Speedometer reads 60 mph60.060.0+0.0 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.0 mph

With 225/45R17 on a car calibrated for 295/30R18, the speedometer reads 60.0 mph when you're really doing 60, and the odometer under-counts by 0.0%.

Speedo showsActual speed
30 mph30.0 mph
45 mph45.0 mph
60 mph60.0 mph
70 mph70.0 mph
80 mph80.0 mph

Other sizes close to 295/30R18

Questions

Can I replace 295/30R18 with 225/45R17?

225/45R17 is a safe swap for 295/30R18 by the usual ±3% rule: the diameter differs by +0.02%.

What's the difference between 295/30R18 and 225/45R17?

225/45R17 is 0.00" taller and 70 mm narrower; the sidewall is +0.50". At an indicated 60 mph you'd actually be doing 60.0 mph.

Will 225/45R17 fit on 295/30R18 wheels?

No — 295/30R18 needs a 18" wheel and 225/45R17 a 17" wheel. This is a plus/minus-size swap that changes wheels too.