CarSpecsHQ

245/45R17 vs 225/50R17

225/50R17 is a safe swap for 245/45R17 by the usual ±3% rule: the diameter differs by +0.69%.

17" rim
245/45R17 25.68" · 225/50R17 25.86" · drawn to scale

Side by side

245/45R17225/50R17Difference
Overall diameter25.68"25.86"+0.18" (+0.69%)
Section width245 mm225 mm-20 mm
Sidewall4.34"4.43"+0.09"
Rim17"17"same
Circumference80.7"81.2"+0.6"
Revs per mile785780-5
Ride height——+0.09"
Speedometer reads 60 mph60.060.4+0.4 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.4 mph

With 225/50R17 on a car calibrated for 245/45R17, the speedometer reads 59.6 mph when you're really doing 60, and the odometer under-counts by 0.7%.

Speedo showsActual speed
30 mph30.2 mph
45 mph45.3 mph
60 mph60.4 mph
70 mph70.5 mph
80 mph80.6 mph

Other sizes close to 245/45R17

Questions

Can I replace 245/45R17 with 225/50R17?

225/50R17 is a safe swap for 245/45R17 by the usual ±3% rule: the diameter differs by +0.69%.

What's the difference between 245/45R17 and 225/50R17?

225/50R17 is 0.18" taller and 20 mm narrower; the sidewall is +0.09". At an indicated 60 mph you'd actually be doing 60.4 mph.

Will 225/50R17 fit on 245/45R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 225 mm tire and the fender clearance.