My Tire Guide

245/40R20 tire size

A 245/40R20 tire stands 27.7 inches tall and 9.6 inches wide, with a 3.9-inch sidewall on a 20-inch rim.

27.7″OVERALL 27.7 IN · RIM 20 IN9.6″3.9″WIDTH · SIDEWALL
Overall height
27.7 in704 mm
Section width
9.6 in245 mm
Sidewall height
3.9 in98 mm
Rim diameter
20 in508 mm
Circumference
87.1 in2212 mm
Revolutions per mile
728452 per km
Inch size
27.7x9.6R20

Compare it with any other size in the tire size calculator.

Sizes you can swap to

These 20-inch sizes are within two width steps and 3% of a 245/40R20's overall height, the usual limit before the speedometer, ABS and transmission notice. The closest is 225/45R20, 0.9% taller (0.26 in). Wider sizes also need room in the wheel well and a rim width that suits them.

SizeHeightWidthAt 60 mph
225/45R20+0.9%+0.26 in−20 mm60.6 mph
235/40R20−1.1%−0.31 in−10 mm59.3 mph
255/40R20+1.1%+0.31 in+10 mm60.7 mph
265/35R20−1.5%−0.41 in+20 mm59.1 mph
235/45R20+2.2%+0.61 in−10 mm61.3 mph
265/40R20+2.3%+0.63 in+20 mm61.4 mph
225/40R20−2.3%−0.63 in−20 mm58.6 mph
255/35R20−2.5%−0.69 in+10 mm58.5 mph

Plus and minus sizes

Changing rim size means changing the sidewall to keep the same overall height. On 18-inch or 19-inch or 21-inch or 22-inch rims, these are the closest matches to a 245/40R20.

SizeHeightWidthAt 60 mph
225/55R18+0.1%+0.03 in−20 mm60.1 mph
245/45R19−0.1%−0.04 in±0 mm59.9 mph
245/35R21+0.1%+0.04 in±0 mm60.1 mph
225/35R22+1.7%+0.48 in−20 mm61.0 mph

Other 20-inch sizes near 245/40R20

245 mm wide, other sidewalls

40 series, other widths

See the other sizes for this rim on 20-inch tire sizes.

Shop 245/40R20 tires

These open each store's own list of 245/40R20 tires, where you can filter by type, load and speed rating.

245/40R20 questions

How tall is a 245/40R20 tire?

About 27.7 inches (704 mm) from the ground to the top of the tread, unloaded. On the vehicle, carrying weight, it sits a little lower.

What does 245/40R20 mean?

245 is the section width in millimetres (9.6 in). 40 means the sidewall is 40% of that width: 98 mm, or 3.9 in. R means radial construction, and 20 is the rim diameter in inches.

Can I use 255/40R20 instead of 245/40R20?

255/40R20 is 1.1% taller (0.31 in) and 10 mm wider, which is inside the usual 3% rule. With it fitted, the speedometer shows 60 mph when you are doing 60.7 mph. Make sure the extra width clears the suspension and fender liner at full lock.

What is 245/40R20 in inches?

In inch terms it is 27.7x9.6R20: 27.7 inches tall, 9.6 inches wide, for a 20-inch rim.

How many revolutions per mile does a 245/40R20 make?

About 728 turns per mile, worked out from its unloaded circumference of 87.1 inches. Makers list slightly higher numbers for their own tires, because a loaded tire rolls on a smaller radius.