275/45R20 in inches

A 275/45R20 tire is 29.7″ tall and 10.8″ wide, and fits a 20″ wheel. In inches it is written 29.7×10.8R20.

Diameter29.74″

Width10.83″

Sidewall4.87″

Drawn to scale. Nominal dimensions calculated from the size code.

Manufacturer data

How tall 275/45R20 tires really are

Heights published by BFGoodrich, General, Michelin and Toyo for all 21 tires in this size. Their published revolutions per mile work out to 28.9″ under load (below).

Real 275/45R20 tires measure 29.70–29.80″, against 29.74″ from the size code. They run both taller and shorter than the size code.

Height under load28.9″

Published revs per mile (698–699) mean the tire rolls like a 28.9″ tire on the vehicle. Use this for speedometer calibration.

Weight spread30.4–38.6 lb

The lightest (Michelin Pilot Sport 4 SUV, XL) is 8.2 lb lighter per corner than the heaviest (Michelin Pilot Alpin 5, XL).

21 tires in 275/45R20

Sort by the spec you care about.

	Load					Revs/mi	Source
Michelin Pilot Sport 4 SUVPerformance	XL · 110V	29.80	30.4	9.5	2,337	699	Spec page
Michelin Pilot Sport All-Season 4Performance	XL · 110Y	29.80	31.1	10.0	2,337	699	Spec page
Michelin Pilot Sport 5Performance	XL · 110(Y)	29.80	31.6	9.0	2,337	699	Spec page
Michelin X-Ice SnowWinter	XL · 110T	29.76	32.6	10.5	2,337	699	Spec page
Michelin CrossClimate2All-season	XL · 110V	29.70	32.7	10.0	2,337	699	Spec page
Michelin Pilot Sport EVPerformance	XL · 110Y	29.80	32.9	8.0	2,337	699	Spec page
Michelin X-Ice Snow+Winter	XL · 110H	29.76	32.9	10.5	2,337	699	Spec page
Toyo Proxes Sport 2Performance	XL · 110Y	29.80	33.1	9.2	2,337	698	Spec page
Michelin Pilot Sport 4 SUVPerformance	XL · 110Y	29.80	33.3	9.5	2,337	699	Spec page
Toyo Celsius SportPerformance	XL · 110Y	29.76	33.7	9.7	2,337	698	Spec page
General G-MAX AS07Performance	XL · 110V	29.70	33.7	11.0	2,337	698	Spec page
Michelin Latitude SportPerformance	XL · 110Y	29.80	34.0	8.5	2,124	699	Spec page
Michelin Latitude Alpin LA2Winter	XL · 110V	29.76	34.2	10.0	2,337	699	Spec page
Toyo Proxes ST IIIPerformance	XL · 110V	29.76	34.8	10.1	2,337	698	Spec page
Michelin Latitude Sport 3Performance	XL · 110V	29.80	34.8	8.5	2,337	699	Spec page
Michelin Pilot Alpin 5Winter	XL · 110V	29.76	35.0	10.5	2,337	699	Spec page
Toyo Observe G3-IceWinter	SL · 106T	29.76	35.7	12.0	2,094	698	Spec page
General Grabber H/THighway	XL · 110V	29.70	35.9	11.0	2,337	698	Spec page
BFGoodrich Advantage ControlAll-season	XL · 110V	29.76	36.3	10.5	2,337	699	Spec page
Toyo Proxes G-Tour	XL · 110V	29.80	36.4	12.1	2,337	698	Spec page
Michelin Pilot Alpin 5Winter	XL · 110V	29.76	38.6	10.5	2,337	699	Spec page

Is 275/45R20 a 30-inch tire?

≈30″

Yes. The size code works out to 29.74″, and the 21 tires here publish 29.70–29.80″, so people call it a 30.

All 30-inch tire sizes, on every wheel size.

Compare with nearby sizes

Differences in overall diameter, calculated from each size code.

Size	Diameter ″	vs 275/45R20	Difference
235/50R20	29.25	-0.49″	-1.7%
295/40R20	29.29	-0.45″	-1.5%
265/45R20	29.39	-0.35″	-1.2%
305/40R20	29.61	-0.14″	-0.5%
245/50R20	29.65	-0.10″	-0.3%
255/50R20	30.04	+0.30″	+1.0%
285/45R20	30.10	+0.35″	+1.2%
235/55R20	30.18	+0.43″	+1.5%
265/50R20	30.43	+0.69″	+2.3%
295/45R20	30.45	+0.71″	+2.4%

How to read 275/45R20

How to read any tire size

How 275/45R20 110V is printed on the sidewall. It's the most common code among the 21 tires here (11 of them); tires in this size come in other load and speed ratings too.

1275Section width

275 mm across the widest point, or 10.83 inches. Every 275 size

245Aspect ratio

A percentage, not a measurement: the sidewall is 45% as tall as the tire is wide, which is 123.8 mm or 4.87 inches.

3RConstruction

Radial construction.

420Wheel diameter

Mounts on a 20-inch wheel. Approved wheel widths run 8.5″ to 10.5″.

5110Load index

Each tire carries up to 2,337 lb (1,060 kg) at its maximum pressure.

6VSpeed rating

Rated for up to 149 mph sustained.

XLExtra load

Printed after the size. In this size the XL tires carry up to 2,337 lb each and the standard-load tires up to 2,094 lb, as published.

Specification	Inches	Metric
Overall diameter	29.74	756 mm
Section width	10.83	275 mm
Sidewall height	4.87	123.8 mm
Circumference	93.4	2,373 mm
Revolutions per mile (calculated, unloaded)	678.1	421 per km
Revolutions per mile (published by manufacturers)	698–699	434 per km
Approved wheel width	8.5–10.5	216–267 mm

Speedometer error after switching to 275/45R20

Your actual speed– mph

Questions about 275/45R20

What is 275/45R20 in inches?

29.74 inches tall, 10.83 inches wide, on a 20-inch wheel. Written in inches, that is roughly 29.7×10.8R20.

How much does a 275/45R20 tire weigh?

Between 30.4 lb and 38.6 lb for the 21 tires listed here. The lightest is the Michelin Pilot Sport 4 SUV (XL); the heaviest is the Michelin Pilot Alpin 5 (XL).

What wheel width do I need for 275/45R20?

Manufacturers approve 8.5–10.5″ wide wheels for this size.

How many revolutions per mile does a 275/45R20 make?

Published figures run 698–699 revolutions per mile. The calculated figure is 678.1, but manufacturers measure the tire under load, where it rolls on a smaller radius.

How much taller is 275/45R20 than 245/50R20?

0.10 inches taller on paper (29.74″ vs 29.65″), which raises the axle about 0.05″. Your speedometer will read about 0.3% slow.