The new tire changes overall diameter by +0.1%. With a speedometer calibrated to the original tire, that same percentage is how far the speedometer and odometer read off — a taller tire means your true speed is higher than indicated and the odometer under-counts distance.
| Speedo shows | True speed | Speedo shows | True speed |
|---|---|---|---|
| 40 km/h | 40 km/h | 25 mph | 25 mph |
| 60 km/h | 60.1 km/h | 37 mph | 37 mph |
| 80 km/h | 80.1 km/h | 50 mph | 50 mph |
| 100 km/h | 100.1 km/h | 62 mph | 62 mph |
| 120 km/h | 120.1 km/h | 75 mph | 75 mph |
Commonly compared with 205/70R15
- 205/70R15 vs 215/60R16 · 215/60R16 specs
- 205/70R15 vs 225/60R16 · 225/60R16 specs
- 205/70R15 vs 215/70R15 · 215/70R15 specs
- 205/70R15 vs 205/60R16 · 205/60R16 specs
- 205/70R15 vs 215/65R16 · 215/65R16 specs
- 205/70R15 vs 235/60R16 · 235/60R16 specs
- 205/70R15 vs 205/65R15 · 205/65R15 specs
- 205/70R15 vs 215/55R16 · 215/55R16 specs
FAQ
What is the overall diameter of a 205/70R15 tire?
A 205/70R15 tire has an overall diameter of about 26.30 inches (668 mm) and a section width of 205 mm.
What sizes can replace a 205/70R15 tire?
Sizes within about ±3% of 205/70R15's 26.3-inch diameter are the closest matches, such as 215/60R16, 225/60R16, 215/70R15. Use the calculator above to check the exact speedometer effect of any substitute.
Fitment & trouble codes
Changing tire size by more than about 3% shifts the speedometer, odometer and, on some vehicles, ABS/traction calibration — which can set wheel-speed-sensor or vehicle-speed codes. See C1234 (wheel speed sensor) and C0050 (rear wheel speed) if a warning light appears after a size change.