215/35R18 tire size
215/35R18 is a metric size: 23.9" tall, 8.5" wide, on a 18" rim — about a 24x8.50R18. The sidewall is 3.0" and the tire turns 843 times per mile.
215/35R18 specs
| Overall diameter (height) | 23.93" · 608 mm |
|---|---|
| Section width | 8.46" · 215 mm |
| Sidewall height | 2.96" · 75 mm (35% of width) |
| Rim diameter | 18" |
| Circumference | 75.16" · 1.909 m |
| Revolutions per mile | 843 (524 per km) |
| Inch (flotation) equivalent | 24x8.50R18 |
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 | |
|---|---|---|---|---|---|
| 225/40R18 common | 25.09" | +4.85% | +10 mm | 62.9 mph | calculate → |
| 255/35R18 common | 25.03" | +4.61% | +40 mm | 62.8 mph | calculate → |
| 245/35R18 common | 24.75" | +3.46% | +30 mm | 62.1 mph | calculate → |
| 215/40R18 | 24.77" | +3.54% | 0 mm | 62.1 mph | calculate → |
| 295/30R18 | 24.97" | +4.36% | +80 mm | 62.6 mph | calculate → |
| 285/30R18 | 24.73" | +3.37% | +70 mm | 62.0 mph | calculate → |
| 205/40R18 | 24.46" | +2.22% | -10 mm | 61.3 mph | calculate → |
| 225/35R18 | 24.20" | +1.15% | +10 mm | 60.7 mph | calculate → |
| 235/35R18 | 24.48" | +2.30% | +20 mm | 61.4 mph | calculate → |
| 205/35R18 | 23.65" | -1.15% | -10 mm | 59.3 mph | calculate → |
| 235/30R18 | 23.55" | -1.56% | +20 mm | 59.1 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 | |
|---|---|---|---|---|---|
| 215/40R17 | 23.77" | -0.64% | 0 mm | 59.6 mph | calculate → |
| 225/40R17 | 24.09" | +0.67% | +10 mm | 60.4 mph | calculate → |
| 195/45R17 | 23.91" | -0.07% | -20 mm | 60.0 mph | calculate → |
| 245/35R17 | 23.75" | -0.72% | +30 mm | 59.6 mph | calculate → |
Try another size against 215/35R18
Questions
What size is 215/35R18 in inches?
215/35R18 is about 23.9" tall and 8.5" wide on a 18-inch rim — roughly a 24x8.50R18 in inch sizing.
What does 215/35R18 mean?
215 mm section width, sidewall 35% of the width (2.96"), radial construction, 18-inch rim.
What tire sizes are equivalent to 215/35R18?
On the same 18" rim, within 3% of the diameter: 205/35R18 (-1.15%), 225/35R18 (+1.15%), 235/30R18 (-1.56%), 205/40R18 (+2.22%), 235/35R18 (+2.30%), 285/30R18 (+3.37%).
How many revolutions per mile does a 215/35R18 tire make?
About 843 revolutions per mile (circumference 75.2").
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.