Fuel cost calculator
Estimate how much you will spend on gas or diesel for a drive: enter one-way distance, realistic fuel economy (MPG or L/100 km), and the price you pay per gallon or liter. Toggle round trip to double the distance automatically.
Trip inputs
Estimate
Fuel volume
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Estimated fuel cost
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For planning only—actual use at the pump varies with driving conditions and vehicle load.
From distance and economy to a rough fuel budget
Most trip-cost questions boil down to two ideas: how far you drive and how much fuel you burn per mile or per hundred kilometers. Multiply fuel volume by the price you expect to pay, and you have a simple scenario for cash planning. This page does not know your tire pressure, headwinds, or the grade of every hill; it trusts the economy number you type, so use a realistic figure from past trips or your vehicle’s long-term average if you track it.
In metric markets, liters per 100 km is a common consumption format: lower numbers mean thriftier driving. In North America, miles per gallon moves in the opposite visual direction (higher is better). If you need to sanity-check a conversion, remember that MPG × L/100 km ≈ 235.2 for gasoline math (using U.S. gallons), but you do not need that identity to use the calculator—just stay inside one unit system per run.
When a fuel-only estimate is still useful
Car-pool organizers use a quick fuel model to split costs fairly before anyone opens a payment app. Freelancers sketch per-mile fuel for a deductible mileage diary’s fuel component (rules vary by jurisdiction—this page is not tax advice). Families compare flying versus driving for vacation by isolating the variable they control at the pump. In each case the goal is a transparent story: distance × consumption × price, with assumptions spelled out in the open.
Frequently asked questions
- How is total fuel cost calculated?
- In U.S. units, gallons equal total miles divided by MPG, and cost equals gallons times price per gallon. In metric units, liters equal (total km ÷ 100) times L/100 km, and cost equals liters times price per liter. Round trip doubles the one-way distance before those steps.
- Does this include tolls, wear on the car, or insurance?
- No. It only estimates fuel volume from your distance and economy assumptions, then multiplies by the price you enter. Real trip cost includes maintenance, depreciation, tolls, and parking, which are not modeled here.
- Why might my result differ from the gas pump?
- Real MPG or L/100 km varies with driving style, traffic, terrain, load, and weather. The economy figure you enter should be your best estimate for the trip, not a brochure ideal.
- Can I switch between MPG and liters per 100 km?
- Use the units selector: U.S. mode expects miles and MPG with price per gallon; metric mode expects kilometers and L/100 km with price per liter.