335/30R21 in inches

A 335/30R21 tire is 28.9″ tall and 13.2″ wide, and fits a 21″ wheel. In inches it is written 28.9×13.2R21.

Diameter28.91″

Width13.19″

Sidewall3.96″

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

Manufacturer data

How tall 335/30R21 tires really are

Heights published by Michelin for all 5 tires in this size. Their published revolutions per mile work out to 28.1″ under load (below).

Real 335/30R21 tires measure 28.90″, against 28.91″ from the size code. They run both taller and shorter than the size code.

Height under load28.1″

Published revs per mile (719) mean the tire rolls like a 28.1″ tire on the vehicle. Use this for speedometer calibration.

Weight spread31.6–36.1 lb

The lightest (Michelin Pilot Sport Cup 2 R, XL) is 4.5 lb lighter per corner than the heaviest (Michelin Pilot Sport S 5, XL).

5 tires in 335/30R21

Sort by the spec you care about.

	Load					Revs/mi	Source
Michelin Pilot Sport Cup 2 RPerformance	XL · 109(Y)	28.90	31.6	5.5	2,271	719	Spec page
Michelin Pilot Sport Cup 2 ConnectPerformance	XL · 109(Y)	28.90	33.3	7.2	2,271	719	Spec page
Michelin Pilot Sport S 5Performance	XL · 109(Y)	28.90	35.0	8.5	2,271	719	Spec page
Michelin Pilot Sport Cup 2 ConnectPerformance	XL · 109(Y)	28.90	35.9	7.2	2,271	719	Spec page
Michelin Pilot Sport S 5Performance	XL · 109(Y)	28.90	36.1	9.0	2,271	719	Spec page

Is 335/30R21 a 29-inch tire?

≈29″

Yes. The size code works out to 28.91″, and the 5 tires here publish 28.90″, so people call it a 29.

All 29-inch tire sizes, on every wheel size.

Compare with nearby sizes

Differences in overall diameter, calculated from each size code.

Size	Diameter ″	vs 335/30R21	Difference
275/35R21	28.58	-0.33″	-1.2%
325/30R21	28.68	-0.24″	-0.8%
245/40R21	28.72	-0.20″	-0.7%
285/35R21	28.85	-0.06″	-0.2%
225/45R21	28.97	+0.06″	+0.2%
255/40R21	29.03	+0.12″	+0.4%
295/35R21	29.13	+0.22″	+0.7%
345/30R21	29.15	+0.24″	+0.8%
235/45R21	29.33	+0.41″	+1.4%
265/40R21	29.35	+0.43″	+1.5%

How to read 335/30R21

How to read any tire size

How 335/30R21 109Y is printed on the sidewall. It's the most common code among the 5 tires here; tires in this size come in other load and speed ratings too.

1335Section width

335 mm across the widest point, or 13.19 inches. Every 335 size

230Aspect ratio

A percentage, not a measurement: the sidewall is 30% as tall as the tire is wide, which is 100.5 mm or 3.96 inches.

3RConstruction

Radial construction.

421Wheel diameter

Mounts on a 21-inch wheel. Approved wheel widths run 11.5″ to 12.5″.

5109Load index

Each tire carries up to 2,271 lb (1,030 kg) at its maximum pressure.

6YSpeed rating

Rated for up to 186 mph sustained.

XLExtra load

Printed after the size.

Specification	Inches	Metric
Overall diameter	28.91	734 mm
Section width	13.19	335 mm
Sidewall height	3.96	100.5 mm
Circumference	90.8	2,307 mm
Revolutions per mile (calculated, unloaded)	697.5	433 per km
Revolutions per mile (published by manufacturers)	719	447 per km
Approved wheel width	11.5–12.5	292–318 mm

Speedometer error after switching to 335/30R21

Your actual speed– mph

Questions about 335/30R21

What is 335/30R21 in inches?

28.91 inches tall, 13.19 inches wide, on a 21-inch wheel. Written in inches, that is roughly 28.9×13.2R21.

How much does a 335/30R21 tire weigh?

Between 31.6 lb and 36.1 lb for the 5 tires listed here. The lightest is the Michelin Pilot Sport Cup 2 R (XL); the heaviest is the Michelin Pilot Sport S 5 (XL).

What wheel width do I need for 335/30R21?

Manufacturers approve 11.5–12.5″ wide wheels for this size.

How many revolutions per mile does a 335/30R21 make?

Published figures run 719 revolutions per mile. The calculated figure is 697.5, but manufacturers measure the tire under load, where it rolls on a smaller radius.

How much taller is 335/30R21 than 285/35R21?

0.06 inches taller on paper (28.91″ vs 28.85″), which raises the axle about 0.03″. Your speedometer will read about 0.2% slow.