235/70R15 vs 235/65R16

Q: Can I replace 235/70R15 with 235/65R16?

235/65R16 is a safe swap for 235/70R15 by the usual ±3% rule: the diameter differs by +0.27%.

235/65R16 is a safe swap for 235/70R15 by the usual ±3% rule: the diameter differs by +0.27%.

235/70R15 27.95" · 235/65R16 28.03" · drawn to scale

Side by side

	235/70R15	235/65R16	Difference
Overall diameter	27.95"	28.03"	+0.07" (+0.27%)
Section width	235 mm	235 mm	0 mm
Sidewall	6.48"	6.01"	-0.46"
Rim	15"	16"	+1"
Circumference	87.8"	88.1"	+0.2"
Revs per mile	722	720	-2
Ride height	—	—	+0.04"
Speedometer reads 60 mph	60.0	60.2	+0.2 mph

Speedometer and odometer

With 235/65R16 on a car calibrated for 235/70R15, the speedometer reads 59.8 mph when you're really doing 60, and the odometer under-counts by 0.3%.

Speedo shows	Actual speed
30 mph	30.1 mph
45 mph	45.1 mph
60 mph	60.2 mph
70 mph	70.2 mph
80 mph	80.2 mph

Other sizes close to 235/70R15

Questions

Can I replace 235/70R15 with 235/65R16?

235/65R16 is a safe swap for 235/70R15 by the usual ±3% rule: the diameter differs by +0.27%.

What's the difference between 235/70R15 and 235/65R16?

235/65R16 is 0.07" taller and 0 mm wider; the sidewall is -0.46". At an indicated 60 mph you'd actually be doing 60.2 mph.

Will 235/65R16 fit on 235/70R15 wheels?

No — 235/70R15 needs a 15" wheel and 235/65R16 a 16" wheel. This is a plus/minus-size swap that changes wheels too.