305/35R23 tire size
305/35R23 is a metric size: 31.4" tall, 12.0" wide, on a 23" rim — about a 31.5x12.00R23. The sidewall is 4.2" and the tire turns 642 times per mile.
305/35R23 specs
| Overall diameter (height) | 31.41" · 798 mm |
|---|---|
| Section width | 12.01" · 305 mm |
| Sidewall height | 4.20" · 107 mm (35% of width) |
| Rim diameter | 23" |
| Circumference | 98.66" · 2.506 m |
| Revolutions per mile | 642 (399 per km) |
| Inch (flotation) equivalent | 31.5x12.00R23 |
Equivalent sizes on a 23" rim
Sizes within ±5% of the overall diameter. Green rows are inside the usual ±3% limit for keeping the speedometer, ABS and gearing right; red rows are bigger changes that need clearance checks.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 285/35R23 | 30.85" | -1.76% | -20 mm | 58.9 mph | calculate → |
| 285/40R23 | 31.98" | +1.82% | -20 mm | 61.1 mph | calculate → |
| 295/35R23 | 31.13" | -0.88% | -10 mm | 59.5 mph | calculate → |
| 325/30R23 | 30.68" | -2.32% | +20 mm | 58.6 mph | calculate → |
| 325/35R23 | 31.96" | +1.76% | +20 mm | 61.1 mph | calculate → |
| 275/40R23 | 31.66" | +0.81% | -30 mm | 60.5 mph | calculate → |
| 255/40R23 | 31.03" | -1.19% | -50 mm | 59.3 mph | calculate → |
| 335/30R23 | 30.91" | -1.57% | +30 mm | 59.1 mph | calculate → |
| 275/35R23 | 30.58" | -2.63% | -30 mm | 58.4 mph | calculate → |
Try another size against 305/35R23
Questions
What size is 305/35R23 in inches?
305/35R23 is about 31.4" tall and 12.0" wide on a 23-inch rim — roughly a 31.5x12.00R23 in inch sizing.
What does 305/35R23 mean?
305 mm section width, sidewall 35% of the width (4.20"), radial construction, 23-inch rim.
What tire sizes are equivalent to 305/35R23?
On the same 23" rim, within 3% of the diameter: 275/40R23 (+0.81%), 295/35R23 (-0.88%), 255/40R23 (-1.19%), 335/30R23 (-1.57%), 285/35R23 (-1.76%), 325/35R23 (+1.76%).
How many revolutions per mile does a 305/35R23 tire make?
About 642 revolutions per mile (circumference 98.7").
How these numbers are computed
Diameter = rim + 2 × sidewall, sidewall = width × aspect ÷ 100, circumference = π × diameter, revolutions per mile = 63,360 ÷ circumference. Real tires differ by brand by a few tenths of an inch. Last reviewed October 14, 2026.