185/70R15 tire size
185/70R15 is a metric size: 25.2" tall, 7.3" wide, on a 15" rim — about a 25x7.50R15. The sidewall is 5.1" and the tire turns 800 times per mile.
185/70R15 specs
| Overall diameter (height) | 25.20" · 640 mm |
|---|---|
| Section width | 7.28" · 185 mm |
| Sidewall height | 5.10" · 130 mm (70% of width) |
| Rim diameter | 15" |
| Circumference | 79.16" · 2.011 m |
| Revolutions per mile | 800 (497 per km) |
| Inch (flotation) equivalent | 25x7.50R15 |
Equivalent sizes on a 15" 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 | |
|---|---|---|---|---|---|
| 195/65R15 common | 24.98" | -0.86% | +10 mm | 59.5 mph | calculate → |
| 205/65R15 common | 25.49" | +1.17% | +20 mm | 60.7 mph | calculate → |
| 185/65R15 common | 24.47" | -2.89% | 0 mm | 58.3 mph | calculate → |
| 195/60R15 common | 24.21" | -3.91% | +10 mm | 57.7 mph | calculate → |
| 175/65R15 | 23.96" | -4.92% | -10 mm | 57.0 mph | calculate → |
| 205/70R15 | 26.30" | +4.38% | +20 mm | 62.6 mph | calculate → |
| 205/60R15 | 24.69" | -2.03% | +20 mm | 58.8 mph | calculate → |
| 215/65R15 | 26.00" | +3.20% | +30 mm | 61.9 mph | calculate → |
| 215/60R15 | 25.16" | -0.16% | +30 mm | 59.9 mph | calculate → |
| 235/60R15 | 26.10" | +3.59% | +50 mm | 62.2 mph | calculate → |
| 195/70R15 | 25.75" | +2.19% | +10 mm | 61.3 mph | calculate → |
| 275/50R15 | 25.83" | +2.50% | +90 mm | 61.5 mph | calculate → |
| 225/60R15 | 25.63" | +1.72% | +40 mm | 61.0 mph | calculate → |
| 26x10.00R15 | 26.00" | +3.19% | +69 mm | 61.9 mph | calculate → |
| 245/50R15 | 24.65" | -2.19% | +60 mm | 58.7 mph | calculate → |
| 345/35R15 | 24.51" | -2.73% | +160 mm | 58.4 mph | calculate → |
| 26x8.50R15 | 26.00" | +3.19% | +31 mm | 61.9 mph | calculate → |
| 265/50R15 | 25.43" | +0.94% | +80 mm | 60.6 mph | calculate → |
| 155/80R15 | 24.76" | -1.72% | -30 mm | 59.0 mph | calculate → |
| 24.5x8.00R15 | 24.50" | -2.77% | +18 mm | 58.3 mph | calculate → |
| 26x10.50R15 | 26.00" | +3.19% | +82 mm | 61.9 mph | calculate → |
| 26x12.00R15 | 26.00" | +3.19% | +120 mm | 61.9 mph | calculate → |
| 26x6.00R15 | 26.00" | +3.19% | -33 mm | 61.9 mph | calculate → |
| 26x7.50R15 | 26.00" | +3.19% | +6 mm | 61.9 mph | calculate → |
| 26x8.00R15 | 26.00" | +3.19% | +18 mm | 61.9 mph | calculate → |
| 235/50R15 | 24.25" | -3.75% | +50 mm | 57.7 mph | calculate → |
| 165/80R15 | 25.39" | +0.78% | -20 mm | 60.5 mph | calculate → |
| 225/55R15 | 24.74" | -1.80% | +40 mm | 58.9 mph | calculate → |
| 165R15 | 25.65" | +1.81% | -20 mm | 61.1 mph | calculate → |
| 175/70R15 | 24.65" | -2.19% | -10 mm | 58.7 mph | calculate → |
| 26x11.50R15 | 26.00" | +3.19% | +107 mm | 61.9 mph | calculate → |
Plus / minus sizing: 14" and 16" rims
Same overall height on a different rim. Check wheel width and clearance before switching.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 215/55R16 common | 25.31" | +0.45% | +30 mm | 60.3 mph | calculate → |
| 195/60R16 | 25.21" | +0.06% | +10 mm | 60.0 mph | calculate → |
| 205/70R14 | 25.30" | +0.41% | +20 mm | 60.2 mph | calculate → |
| 235/60R14 | 25.10" | -0.38% | +50 mm | 59.8 mph | calculate → |
| 145/80R16 | 25.13" | -0.25% | -40 mm | 59.8 mph | calculate → |
| 175R14 | 25.30" | +0.41% | -10 mm | 60.2 mph | calculate → |
| 265/45R16 | 25.39" | +0.77% | +80 mm | 60.5 mph | calculate → |
Try another size against 185/70R15
Questions
What size is 185/70R15 in inches?
185/70R15 is about 25.2" tall and 7.3" wide on a 15-inch rim — roughly a 25x7.50R15 in inch sizing.
What does 185/70R15 mean?
185 mm section width, sidewall 70% of the width (5.10"), radial construction, 15-inch rim.
What tire sizes are equivalent to 185/70R15?
On the same 15" rim, within 3% of the diameter: 215/60R15 (-0.16%), 165/80R15 (+0.78%), 195/65R15 (-0.86%), 265/50R15 (+0.94%), 205/65R15 (+1.17%), 225/60R15 (+1.72%).
How many revolutions per mile does a 185/70R15 tire make?
About 800 revolutions per mile (circumference 79.2").
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.