265/30R22 vs 265/35R21

Q: Can I replace 265/30R22 with 265/35R21?

265/35R21 is a safe swap for 265/30R22 by the usual ±3% rule: the diameter differs by +0.15%.

265/35R21 is a safe swap for 265/30R22 by the usual ±3% rule: the diameter differs by +0.15%.

265/30R22 28.26" · 265/35R21 28.30" · drawn to scale

Side by side

	265/30R22	265/35R21	Difference
Overall diameter	28.26"	28.30"	+0.04" (+0.15%)
Section width	265 mm	265 mm	0 mm
Sidewall	3.13"	3.65"	+0.52"
Rim	22"	21"	-1"
Circumference	88.8"	88.9"	+0.1"
Revs per mile	714	713	-1
Ride height	—	—	+0.02"
Speedometer reads 60 mph	60.0	60.1	+0.1 mph

Speedometer and odometer

With 265/35R21 on a car calibrated for 265/30R22, the speedometer reads 59.9 mph when you're really doing 60, and the odometer under-counts by 0.2%.

Speedo shows	Actual speed
30 mph	30.0 mph
45 mph	45.1 mph
60 mph	60.1 mph
70 mph	70.1 mph
80 mph	80.1 mph

Other sizes close to 265/30R22

Questions

Can I replace 265/30R22 with 265/35R21?

265/35R21 is a safe swap for 265/30R22 by the usual ±3% rule: the diameter differs by +0.15%.

What's the difference between 265/30R22 and 265/35R21?

265/35R21 is 0.04" taller and 0 mm wider; the sidewall is +0.52". At an indicated 60 mph you'd actually be doing 60.1 mph.

Will 265/35R21 fit on 265/30R22 wheels?

No — 265/30R22 needs a 22" wheel and 265/35R21 a 21" wheel. This is a plus/minus-size swap that changes wheels too.