Tire size fuel-cost calculator
Do bigger tires change my fuel cost?
A taller tire makes the odometer under-read: for every kilometre shown you actually travel slightly more, so your true distance — and the fuel it uses — is higher than the dashboard suggests. This calculator multiplies the odometer error by your annual distance, fuel use and fuel price to estimate the yearly fuel-cost difference. It models only the distance effect, not rolling resistance.
- True annual distance
- 13,049 km
- Annual fuel-cost difference
- +6.30
A taller tire makes the odometer under-read: for every kilometre shown you actually travel slightly more, so your true distance — and the fuel it uses — is higher than the dashboard suggests. This calculator multiplies the odometer error by your annual distance, fuel use and fuel price to estimate the yearly fuel-cost difference. It models only the distance effect, not rolling resistance.
Models only the odometer-distance effect of the size change, not rolling resistance.
Worked examples
This isolates the odometer-distance effect only. It does not claim that a wider or heavier tire has the same rolling resistance.
| Current size | Candidate size | Odometer effect | True distance | Extra fuel at 8 L/100 km |
|---|---|---|---|---|
| 225/45R17 | 235/40R18 | +1.7% | 20300 km | +27.5 L |
| 235/55R18 | 245/50R19 | +1.7% | 20300 km | +26.6 L |
| 265/70R17 | 285/70R17 | +3.5% | 20700 km | +55.8 L |
What to do with it: Add a separate allowance for rolling resistance if the tire is wider or heavier.
More tools
- Tire pressure and fuel economy guide
- Speedometer error calculator
- Tire size calculator
- Tire & wheel reference guides
- Content updated
- 2026-06-23
What changed
- Checked generated routes, metadata, sitemap inclusion and localized page rendering.