CarSpecsHQ

265/45R21 vs 315/35R22

315/35R22 is a safe swap for 265/45R21 by the usual ±3% rule: the diameter differs by +0.96%.

21" → 22"
265/45R21 30.39" · 315/35R22 30.68" · drawn to scale

Side by side

265/45R21315/35R22Difference
Overall diameter30.39"30.68"+0.29" (+0.96%)
Section width265 mm315 mm+50 mm
Sidewall4.69"4.34"-0.35"
Rim21"22"+1"
Circumference95.5"96.4"+0.9"
Revs per mile664657-6
Ride height——+0.15"
Speedometer reads 60 mph60.060.6+0.6 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.6 mph

With 315/35R22 on a car calibrated for 265/45R21, the speedometer reads 59.4 mph when you're really doing 60, and the odometer under-counts by 1.0%.

Speedo showsActual speed
30 mph30.3 mph
45 mph45.4 mph
60 mph60.6 mph
70 mph70.7 mph
80 mph80.8 mph

Other sizes close to 265/45R21

Questions

Can I replace 265/45R21 with 315/35R22?

315/35R22 is a safe swap for 265/45R21 by the usual ±3% rule: the diameter differs by +0.96%.

What's the difference between 265/45R21 and 315/35R22?

315/35R22 is 0.29" taller and 50 mm wider; the sidewall is -0.35". At an indicated 60 mph you'd actually be doing 60.6 mph.

Will 315/35R22 fit on 265/45R21 wheels?

No — 265/45R21 needs a 21" wheel and 315/35R22 a 22" wheel. This is a plus/minus-size swap that changes wheels too.