CarSpecsHQ

245/50R20 vs 265/50R20

265/50R20 is a safe swap for 245/50R20 by the usual ±3% rule: the diameter differs by +2.66%.

20" rim
245/50R20 29.65" · 265/50R20 30.43" · drawn to scale

Side by side

245/50R20265/50R20Difference
Overall diameter29.65"30.43"+0.79" (+2.66%)
Section width245 mm265 mm+20 mm
Sidewall4.82"5.22"+0.39"
Rim20"20"same
Circumference93.1"95.6"+2.5"
Revs per mile680663-18
Ride height——+0.39"
Speedometer reads 60 mph60.061.6+1.6 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.6 mph

With 265/50R20 on a car calibrated for 245/50R20, the speedometer reads 58.4 mph when you're really doing 60, and the odometer under-counts by 2.7%.

Speedo showsActual speed
30 mph30.8 mph
45 mph46.2 mph
60 mph61.6 mph
70 mph71.9 mph
80 mph82.1 mph

Other sizes close to 245/50R20

Questions

Can I replace 245/50R20 with 265/50R20?

265/50R20 is a safe swap for 245/50R20 by the usual ±3% rule: the diameter differs by +2.66%.

What's the difference between 245/50R20 and 265/50R20?

265/50R20 is 0.79" taller and 20 mm wider; the sidewall is +0.39". At an indicated 60 mph you'd actually be doing 61.6 mph.

Will 265/50R20 fit on 245/50R20 wheels?

Both use a 20" rim, so the wheel diameter matches; check the wheel's width range for a 265 mm tire and the fender clearance.