305/35R18 tire size
305/35R18 is a metric size: 26.4" tall, 12.0" wide, on a 18" rim — about a 26.5x12.00R18. The sidewall is 4.2" and the tire turns 764 times per mile.
305/35R18 specs
| Overall diameter (height) | 26.41" · 671 mm |
|---|---|
| Section width | 12.01" · 305 mm |
| Sidewall height | 4.20" · 107 mm (35% of width) |
| Rim diameter | 18" |
| Circumference | 82.96" · 2.107 m |
| Revolutions per mile | 764 (475 per km) |
| Inch (flotation) equivalent | 26.5x12.00R18 |
Equivalent sizes on a 18" 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 | |
|---|---|---|---|---|---|
| 225/45R18 common | 25.97" | -1.64% | -80 mm | 59.0 mph | calculate → |
| 245/40R18 common | 25.72" | -2.61% | -60 mm | 58.4 mph | calculate → |
| 225/40R18 common | 25.09" | -4.99% | -80 mm | 57.0 mph | calculate → |
| 245/45R18 common | 26.68" | +1.04% | -60 mm | 60.6 mph | calculate → |
| 235/50R18 common | 27.25" | +3.21% | -70 mm | 61.9 mph | calculate → |
| 235/45R18 common | 26.33" | -0.30% | -70 mm | 59.8 mph | calculate → |
| 235/40R18 common | 25.40" | -3.80% | -70 mm | 57.7 mph | calculate → |
| 225/50R18 common | 26.86" | +1.71% | -80 mm | 61.0 mph | calculate → |
| 255/40R18 common | 26.03" | -1.42% | -50 mm | 59.2 mph | calculate → |
| 245/50R18 common | 27.65" | +4.70% | -60 mm | 62.8 mph | calculate → |
| 275/35R18 common | 25.58" | -3.13% | -30 mm | 58.1 mph | calculate → |
| 265/35R18 common | 25.30" | -4.17% | -40 mm | 57.5 mph | calculate → |
| 255/45R18 common | 27.04" | +2.39% | -50 mm | 61.4 mph | calculate → |
| 215/55R18 common | 27.31" | +3.43% | -90 mm | 62.1 mph | calculate → |
| 275/40R18 common | 26.66" | +0.97% | -30 mm | 60.6 mph | calculate → |
| 215/45R18 common | 25.62" | -2.98% | -90 mm | 58.2 mph | calculate → |
| 265/40R18 | 26.35" | -0.22% | -40 mm | 59.9 mph | calculate → |
| 285/35R18 | 25.85" | -2.09% | -20 mm | 58.7 mph | calculate → |
| 315/30R18 | 25.44" | -3.65% | +10 mm | 57.8 mph | calculate → |
| 295/35R18 | 26.13" | -1.04% | -10 mm | 59.4 mph | calculate → |
| 335/30R18 | 25.91" | -1.86% | +30 mm | 58.9 mph | calculate → |
| 215/50R18 | 26.46" | +0.22% | -90 mm | 60.1 mph | calculate → |
| 295/40R18 | 27.29" | +3.35% | -10 mm | 62.0 mph | calculate → |
| 265/45R18 | 27.39" | +3.73% | -40 mm | 62.2 mph | calculate → |
| 285/40R18 | 26.98" | +2.16% | -20 mm | 61.3 mph | calculate → |
| 345/35R18 | 27.51" | +4.17% | +40 mm | 62.5 mph | calculate → |
| 305/40R18 | 27.61" | +4.55% | 0 mm | 62.7 mph | calculate → |
| 155/70R18 | 26.54" | +0.52% | -150 mm | 60.3 mph | calculate → |
| 26x12.00R18 | 26.00" | -1.54% | 0 mm | 59.1 mph | calculate → |
| 26x6.00R18 | 26.00" | -1.54% | -153 mm | 59.1 mph | calculate → |
| 26x8.00R18 | 26.00" | -1.54% | -102 mm | 59.1 mph | calculate → |
| 145/70R18 | 25.99" | -1.57% | -160 mm | 59.1 mph | calculate → |
| 325/35R18 | 26.96" | +2.09% | +20 mm | 61.3 mph | calculate → |
| 165/70R18 | 27.09" | +2.61% | -140 mm | 61.6 mph | calculate → |
| 145/80R18 | 27.13" | +2.76% | -160 mm | 61.7 mph | calculate → |
| 155/60R18 | 25.32" | -4.10% | -150 mm | 57.5 mph | calculate → |
| 305/30R18 | 25.20" | -4.55% | 0 mm | 57.3 mph | calculate → |
| 145/85R18 | 27.70" | +4.92% | -160 mm | 63.0 mph | calculate → |
| 345/30R18 | 26.15" | -0.97% | +40 mm | 59.4 mph | calculate → |
| 315/35R18 | 26.68" | +1.04% | +10 mm | 60.6 mph | calculate → |
| 195/60R18 | 27.21" | +3.06% | -110 mm | 61.8 mph | calculate → |
| 205/45R18 | 25.26" | -4.32% | -100 mm | 57.4 mph | calculate → |
| 205/60R18 | 27.69" | +4.85% | -100 mm | 62.9 mph | calculate → |
Plus / minus sizing: 17" and 19" rims
Same overall height on a different rim. Check wheel width and clearance before switching.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 215/55R17 common | 26.31" | -0.36% | -90 mm | 59.8 mph | calculate → |
| 235/40R19 common | 26.40" | -0.01% | -70 mm | 60.0 mph | calculate → |
| 275/35R19 common | 26.58" | +0.66% | -30 mm | 60.4 mph | calculate → |
| 235/50R17 common | 26.25" | -0.58% | -70 mm | 59.7 mph | calculate → |
| 265/35R19 common | 26.30" | -0.39% | -40 mm | 59.8 mph | calculate → |
| 305/30R19 | 26.20" | -0.76% | 0 mm | 59.5 mph | calculate → |
| 245/50R17 | 26.65" | +0.91% | -60 mm | 60.5 mph | calculate → |
| 315/30R19 | 26.44" | +0.13% | +10 mm | 60.1 mph | calculate → |
| 335/35R17 | 26.23" | -0.66% | +30 mm | 59.6 mph | calculate → |
| 195/60R17 | 26.21" | -0.73% | -110 mm | 59.6 mph | calculate → |
| 295/40R17 | 26.29" | -0.43% | -10 mm | 59.7 mph | calculate → |
Try another size against 305/35R18
Questions
What size is 305/35R18 in inches?
305/35R18 is about 26.4" tall and 12.0" wide on a 18-inch rim — roughly a 26.5x12.00R18 in inch sizing.
What does 305/35R18 mean?
305 mm section width, sidewall 35% of the width (4.20"), radial construction, 18-inch rim.
What tire sizes are equivalent to 305/35R18?
On the same 18" rim, within 3% of the diameter: 215/50R18 (+0.22%), 265/40R18 (-0.22%), 235/45R18 (-0.30%), 155/70R18 (+0.52%), 275/40R18 (+0.97%), 345/30R18 (-0.97%).
How many revolutions per mile does a 305/35R18 tire make?
About 764 revolutions per mile (circumference 83.0").
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.