justyourcalculatorGas Mileage Calculator
Your actual MPG or L/100 km from a fill-up, and the cost per mile.
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Gas Mileage Calculator
Your car's real MPG from a fill-up
Fuel economy
29.2 mpg
8.06 L/100 km
- Miles per gallon (US)
- 29.17
- Liters per 100 km
- 8.06
- Kilometers per liter
- 12.4
- Miles per gallon (UK)
- 35.03
- Distance
- 350 mi
- Fuel cost
- $38.40
- Cost per mile
- $0.11
Most accurate when you fill the tank completely both times, so the fuel added equals the fuel used.
How it was calculated
- 350 mi ÷ 12 gal = 29.17 mpg
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How the gas mileage calculator works
Fill the tank, note the odometer, drive, then fill up again. The fuel added the second time is what you used, so MPG = miles driven ÷ gallons added.
Metric economy is usually quoted as liters per 100 km: liters ÷ km × 100. To convert, L/100 km = 235.215 ÷ MPG (US gallons). UK MPG is 1.201 times the US figure because the imperial gallon is larger.
Using and checking your result
Published by JustYourCalculator. Check the units and assumptions above, and compare a known example before relying on the output. Calculations use browser arithmetic and may round displayed values.
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