Fuel Cost Calculator
Gas cost for a trip.
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Gas Mileage Calculator
Enter miles driven and gallons used to get your MPG — plus L/100km and km per litre.
Fuel economy
—
Miles per gallon.
| Litres / 100 km | — |
|---|---|
| Km per litre | — |
| Miles | — |
| Gallons | — |
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Enter your figures above to see the step-by-step working.
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How the Gas Mileage Calculator Works
Fuel economy is simply the miles you drove divided by the gallons you burned. Fill up, note the trip miles, and at the next fill-up divide by the gallons it took to top off — that’s your real-world miles per gallon. This calculator does that and also converts to the metric measures litres per 100 km and kilometres per litre.
Tracking a few tanks gives a better picture than any single fill-up, since driving style, load, weather and traffic all move the number. A rising L/100km or falling MPG can be an early hint of tyre pressure or maintenance issues.
MPG = miles driven ÷ gallons used
Frequently Asked Questions
How do I calculate my gas mileage?
Divide the miles driven by the gallons used to refill. If you went 300 miles on 12 gallons, that’s 25 MPG.
How do I convert MPG to L/100km?
Divide 235.215 by the MPG figure. 25 MPG is about 9.4 litres per 100 km.
Why does my mileage vary?
City driving, hard acceleration, cold weather, extra weight and low tyre pressure all lower fuel economy. Averaging several tanks smooths out the variation.
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