265/50R19 vs 255/55R19

Q: Can I replace 265/50R19 with 255/55R19?

255/55R19 is a safe swap for 265/50R19 by the usual ±3% rule: the diameter differs by +2.07%.

255/55R19 is a safe swap for 265/50R19 by the usual ±3% rule: the diameter differs by +2.07%.

265/50R19 29.43" · 255/55R19 30.04" · drawn to scale

Side by side

	265/50R19	255/55R19	Difference
Overall diameter	29.43"	30.04"	+0.61" (+2.07%)
Section width	265 mm	255 mm	-10 mm
Sidewall	5.22"	5.52"	+0.31"
Rim	19"	19"	same
Circumference	92.5"	94.4"	+1.9"
Revs per mile	685	671	-14
Ride height	—	—	+0.31"
Speedometer reads 60 mph	60.0	61.2	+1.2 mph

Speedometer and odometer

With 255/55R19 on a car calibrated for 265/50R19, the speedometer reads 58.8 mph when you're really doing 60, and the odometer under-counts by 2.1%.

Speedo shows	Actual speed
30 mph	30.6 mph
45 mph	45.9 mph
60 mph	61.2 mph
70 mph	71.5 mph
80 mph	81.7 mph

Other sizes close to 265/50R19

Questions

Can I replace 265/50R19 with 255/55R19?

255/55R19 is a safe swap for 265/50R19 by the usual ±3% rule: the diameter differs by +2.07%.

What's the difference between 265/50R19 and 255/55R19?

255/55R19 is 0.61" taller and 10 mm narrower; the sidewall is +0.31". At an indicated 60 mph you'd actually be doing 61.2 mph.

Will 255/55R19 fit on 265/50R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 255 mm tire and the fender clearance.