CarSpecsHQ

205/75R15 vs 225/75R15

225/75R15 is outside the ±3% rule as a replacement for 205/75R15: the diameter differs by +4.36%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

15" rim
205/75R15 27.11" · 225/75R15 28.29" · drawn to scale

Side by side

205/75R15225/75R15Difference
Overall diameter27.11"28.29"+1.18" (+4.36%)
Section width205 mm225 mm+20 mm
Sidewall6.05"6.64"+0.59"
Rim15"15"same
Circumference85.2"88.9"+3.7"
Revs per mile744713-31
Ride height——+0.59"
Speedometer reads 60 mph60.062.6+2.6 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.6 mph

With 225/75R15 on a car calibrated for 205/75R15, the speedometer reads 57.5 mph when you're really doing 60, and the odometer under-counts by 4.4%.

Speedo showsActual speed
30 mph31.3 mph
45 mph47.0 mph
60 mph62.6 mph
70 mph73.1 mph
80 mph83.5 mph

Other sizes close to 205/75R15

Questions

Can I replace 205/75R15 with 225/75R15?

225/75R15 is outside the ±3% rule as a replacement for 205/75R15: the diameter differs by +4.36%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 205/75R15 and 225/75R15?

225/75R15 is 1.18" taller and 20 mm wider; the sidewall is +0.59". At an indicated 60 mph you'd actually be doing 62.6 mph.

Will 225/75R15 fit on 205/75R15 wheels?

Both use a 15" rim, so the wheel diameter matches; check the wheel's width range for a 225 mm tire and the fender clearance.