Fuel Economy Calculator
Converts distance traveled and fuel used into fuel economy, reporting both miles per gallon and the equivalent liters per 100 kilometers.
What this calculator does
The Fuel Economy Calculator estimates your result instantly from the values you enter, using standard auto loans formulas. Converts distance traveled and fuel used into fuel economy, reporting both miles per gallon and the equivalent liters per 100 kilometers. Calculations run in your browser, so nothing you type is sent to a server, and the output is an estimate for planning rather than financial advice.
Result
About Fuel Economy Calculator
Enter the distance you drove in miles and the fuel you used in gallons, and this calculator returns your fuel economy as miles per gallon (MPG) along with the metric equivalent in liters per 100 kilometers.
MPG is simply miles divided by gallons, and the L/100km figure is derived from that MPG value, so you can read your efficiency in either unit.
Formula & Mathematical Calculation
Miles Per Gallon = f(Distance (miles), Fuel Used (gallons))
Calculated according to standard finance formulas implemented in the calculator core.
Calculation Example
Driving 350 miles on 12 gallons gives 29.17 MPG, which converts to 8.06 L/100km.
Key Benefits
- Reports fuel economy in both MPG and L/100km at once
- Uses only the trip distance and fuel used, with no rates to look up
- Handles any mileage and gallon figures you enter
How to Use this Calculator
-
Enter the distance
Type the miles driven in the Distance (miles) field. -
Enter the fuel used
Type the gallons consumed in the Fuel Used (gallons) field. -
Calculate
Press Calculate to see miles per gallon and the L/100km equivalent.
Assumptions & Limitations
What the calculation assumes
- Every value you enter is treated as an exact, known amount.
- Rates and contributions are assumed to stay constant for the whole period unless the form asks for them separately.
- Results use standard financial formulas and ignore fees, penalties and promotional terms that are not entered above.
- Inflation, tax changes and market volatility are not modelled unless a field for them is provided.
- Amounts are unit-agnostic: results are returned in the same currency you enter.
What it does not cover
- Fuel Economy Calculator produces estimates for education and planning, not a quote, offer or professional advice.
- Real-world outcomes differ when fees, taxes, rounding rules or provider-specific terms apply.
- Local regulations and tax rules vary by country and change over time; verify current rules for your jurisdiction.
- Figures are only as accurate as the inputs you supply — check them before acting on the result.
- For decisions with lasting financial impact, confirm the numbers with a qualified professional.
Frequently Asked Questions
Free to use, no account needed. Calculations run in your browser, so nothing you type is sent to a server. Results are estimates — how we build and check our calculators.
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