Fuel Cost Calculator
Cost per Distance
MPG (US): Miles per gallon - higher is more efficient
km/L: Kilometers per liter - higher is more efficient
L/100km: Liters per 100 kilometers - lower is more efficient
About the Fuel Cost Calculator
The Fuel Cost Calculator estimates how much you will spend on fuel for a trip or over a period by combining the distance traveled, your vehicle's fuel efficiency, and the price of fuel. You enter the trip distance, your car's economy (in miles per gallon, liters per 100 km, or km per liter), and the current price per gallon or liter, and it returns the total fuel cost and the volume of fuel needed. It is ideal for road-trip budgeting, commute cost analysis, and comparing the running cost of different vehicles.
The math is straightforward but easy to get wrong by hand, especially across measurement systems: the tool converts distance into fuel volume using your efficiency figure, then multiplies that volume by the unit price. Because economy can be expressed as miles per gallon (higher is better) or liters per 100 km (lower is better), the calculator handles the inversion automatically so you do not have to flip the ratio yourself. This makes it reliable whether you drive a US vehicle rated in MPG or a European one rated in L/100km.
Common scenarios include planning the fuel budget for a long drive, working out the per-trip cost of a daily commute to decide between driving and transit, splitting fuel costs among carpool riders, and comparing the lifetime running cost of a thirstier versus more efficient car. It also helps quantify how rising pump prices affect your monthly transport spending.
A practical tip is to use your real-world average economy rather than the manufacturer's optimistic sticker figure, since city driving, highway speed, cargo, and weather can swing actual consumption by 20% or more. To convert your car's rating between MPG and L/100km before entering it, or to convert distances and tank volumes, the Volume Converter and Length Converter pair naturally with this calculator.
Frequently asked questions
- What information do I need to calculate fuel cost?
- Three values: the trip distance, your vehicle's fuel efficiency (MPG, L/100km, or km/L), and the price per unit of fuel. The calculator returns total cost and fuel volume.
- How do I convert MPG to L/100km?
- Divide 235.215 by the MPG figure to get L/100km (using US gallons). For example, 30 MPG is about 7.84 L/100km. The calculator accepts either format directly.
- Should I use the manufacturer's MPG rating?
- For accuracy, use your own observed average instead. Real-world economy is often 10–20% worse than the sticker figure due to traffic, speed, climate control, and load.
- Can I use this to split fuel costs for a carpool?
- Yes. Calculate the total trip fuel cost, then divide by the number of passengers to determine each person's fair share.