Gas Mileage Calculator
Calculate your vehicle's gas mileage in miles per gallon (mpg), km/l, and liters/100km.
- Free to use
- Accurate results
- No registration required
- Works on all devices
Enter your distance traveled and fuel used to calculate your gas mileage in mpg, km/l, and liters/100km.
Your result
30 mpg
Miles per gallon (mpg)
Kilometers per liter12.75 km/l
Liters per 100 km7.84 l/100km
AI explanation
Formula
mpg = distance (miles) ÷ fuel used (US gallons)Worked example
300 miles on 10 gallons
| Field | Value |
|---|---|
| Distance traveled | 300 |
| Distance unit | miles |
| Fuel used | 10 |
| Fuel unit | gallons |
| Miles per gallon (mpg) | 30 |
| Kilometers per liter | 12.75 |
| Liters per 100 km | 7.84 |
Assumptions
- Uses US gallons (3.785411784 liters) — UK/imperial gallons are about 20% larger and would give a different mpg figure for the same fuel volume.
- Uses the odometer-reading and fuel-fill method — enter the distance covered by the fuel amount you entered.
Frequently asked questions
Is mpg the same everywhere?
No — US mpg uses US gallons, while UK mpg uses the larger imperial gallon. The same vehicle and fuel usage will show a lower "mpg" figure under the US convention than the UK one. This calculator uses US gallons.
How do I convert mpg to km/l?
Multiply mpg by 0.4251 to get km/l (since 1 mile ≈ 1.609 km and 1 US gallon ≈ 3.785 liters) — or just use this calculator's unit selectors to get both directly.
What's a good mpg for a modern car?
Compact and hybrid cars often exceed 40-50 mpg, midsize sedans typically run 25-35 mpg, and larger SUVs/trucks commonly range 15-25 mpg — real-world figures vary with driving conditions.