Calculate your vehicle's fuel economy instantly. Convert between MPG (US/UK), L/100km, and km/L. Get fuel efficiency ratings and cost estimates. Pure client-side, free, no data collection.
This gas mileage calculator helps you instantly calculate your vehicle's fuel efficiency in multiple units. Whether you need MPG for US measurements, L/100km for European standards, or km/L for Asian markets, get accurate conversions with a clear efficiency rating. All calculations happen client-side — your driving data never leaves your device.
MPG (US) uses US gallons (3.785 liters) while MPG (UK) uses Imperial gallons (4.546 liters). A vehicle getting 30 MPG (US) would get about 36 MPG (UK) because the Imperial gallon is larger.
L/100km is intuitive for consumption (lower is better), while km/L or MPG shows efficiency (higher is better). Europe and China prefer L/100km, the US uses MPG, and Japan/Korea use km/L.
A good fuel efficiency is typically ≤7 L/100km (≥34 MPG US), which is common for efficient sedans and hybrids. ≤5 L/100km (≥47 MPG US) is excellent, while >9 L/100km (<26 MPG US) is considered poor.
The cost estimate is based on the fuel price you enter and your calculated efficiency. It provides a reasonable estimate for budgeting but may not account for real-world driving conditions like traffic, terrain, and driving style.
This calculator is designed for gasoline and diesel vehicles. For electric vehicles, efficiency is measured in kWh/100km or MPGe (miles per gallon equivalent), which requires a different calculation method.