-1.45%Safe swap — speedometer error is minor
Speedometer error
With a speedometer calibrated to 225/70R15, fitting 215/65R16 makes it read as follows:
| Speedo shows | True speed | Speedo shows | True speed |
|---|---|---|---|
| 40 km/h | 39.4 km/h | 25 mph | 24 mph |
| 60 km/h | 59.1 km/h | 37 mph | 37 mph |
| 80 km/h | 78.8 km/h | 50 mph | 49 mph |
| 100 km/h | 98.5 km/h | 62 mph | 61 mph |
| 120 km/h | 118.3 km/h | 75 mph | 73 mph |
Full comparison
225/70R15
Overall diameter696.0 mm · 27.40 in
Section width225 mm · 8.86 in
Sidewall height157.5 mm · 6.20 in
Circumference2186.5 mm · 86.1 in
Revolutions per mile736
Revolutions per km457
215/65R16
Overall diameter685.9 mm · 27.00 in
Section width215 mm · 8.46 in
Sidewall height139.8 mm · 5.50 in
Circumference2154.8 mm · 84.8 in
Revolutions per mile747
Revolutions per km464
-1.45%Safe swap — speedometer error is minor
Original
Overall diameter696 mm · 27.4 in
Sidewall height157.5 mm
Circumference2,186.5 mm
Revolutions / mile736
New
Overall diameter685.9 mm · 27 in
Sidewall height139.8 mm
Circumference2,154.8 mm
Revolutions / mile746.9
Speedometer & odometer error
The new tire changes overall diameter by -1.45%. 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 | 39.4 km/h | 25 mph | 24 mph |
| 60 km/h | 59.1 km/h | 37 mph | 37 mph |
| 80 km/h | 78.8 km/h | 50 mph | 49 mph |
| 100 km/h | 98.5 km/h | 62 mph | 61 mph |
| 120 km/h | 118.3 km/h | 75 mph | 73 mph |
See individual specs: 225/70R15 · 215/65R16. A change this size can affect ABS/speed calibration — see wheel-speed codes if a light appears.