Fuel Cost Calculator
Fuel needed and trip cost for a drive, US or metric.
Fuel Cost Calculator
| Fuel needed (gallons or litres) | 10.00 |
| Trip fuel cost | $36.00 |
A 300-mile trip at 30 mpg uses 10 gallons — $36.00 at $3.60 a gallon.
Plan a trip's fuel budget: enter the distance, your vehicle's efficiency and the fuel price. In US mode efficiency is miles per gallon and price is per gallon; in metric mode efficiency is litres per 100 km and price is per litre.
Real-world efficiency varies with speed, load, terrain and weather, so treat the result as a planning estimate and keep a margin on long trips. If your car quotes km/L instead of L/100km, convert with L/100km = 100 ÷ km/L.
The formula
Worked example
A 300-mile trip at 30 mpg uses 10 gallons — $36.00 at $3.60 a gallon.
The example is pre-loaded in the result panel — press Calculate with your own numbers to replace it.
Frequently asked questions
How do I convert km/L to L/100km?
L/100km = 100 ÷ km/L. A car doing 15 km/L uses 6.67 L/100km. Enter 6.67 in metric mode.
Should I use the manufacturer's mpg figure?
It is a reasonable starting point, but highway driving at high speed, roof boxes and cold weather can cut real efficiency by 10–20%. Lower the figure slightly for a conservative budget.
Category: Everyday Life calculators
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