Estimate how much you'll spend on fuel for any trip — one-way or round trip, metric or imperial.
One-way distance
Your vehicle's consumption
Check your local gas station
A fuel cost calculator is a simple but powerful tool that estimates how much money you will spend on gasoline or diesel for a given trip. Instead of guessing or doing mental arithmetic at the gas station, you enter three values — distance, fuel efficiency, and price per liter or gallon — and the calculator returns an accurate estimate in seconds.
Whether you are planning a weekend road trip, commuting to work five days a week, or comparing the running costs of two different vehicles, this calculator gives you the clarity to make informed decisions. It supports both metric units (kilometers and liters) and imperial units (miles and gallons), covers one-way and round trips, and works in five major currencies.
Fuel is one of the most variable and significant costs of owning a car. For the average driver covering 15,000 km (9,300 miles) per year in a mid-size car consuming 8 L/100km at $1.70/liter, annual fuel spend comes to approximately $2,040. Small improvements in efficiency or route planning can save hundreds of dollars per year — and this calculator helps you see exactly where your money goes.
The metric formula divides by 100 because L/100km expresses consumption per 100 kilometers, not per kilometer. The imperial formula divides distance by MPG because miles-per-gallon is already expressed as distance-per-unit-of-fuel. Both approaches yield the same result when converted correctly.
Using the Fuel Cost Calculator takes under 30 seconds:
The following table shows estimated fuel costs for a 500 km (310 mile) trip at $1.70/liter ($6.44/gallon US) for common vehicle types:
| Vehicle type | Efficiency | Fuel (500 km) | Est. cost |
|---|---|---|---|
| Small city car (e.g. VW Polo) | 5.5 L/100km | 27.5 L | $46.75 |
| Compact hatchback (e.g. Toyota Corolla) | 6.5 L/100km | 32.5 L | $55.25 |
| Mid-size sedan (e.g. Honda Accord) | 8.0 L/100km | 40.0 L | $68.00 |
| Large SUV (e.g. Ford Explorer) | 11.0 L/100km | 55.0 L | $93.50 |
| Full-size pickup truck (e.g. Ford F-150) | 13.5 L/100km | 67.5 L | $114.75 |
| Hybrid (e.g. Toyota Prius) | 4.0 L/100km | 20.0 L | $34.00 |
| Diesel estate (e.g. BMW 3-Series) | 5.0 L/100km | 25.0 L | $42.50 |
Estimates based on $1.70/liter (~€1.55/liter). Actual costs depend on driving style, traffic, road type, and fuel grade.
Anna is driving from Berlin to Munich — a distance of 585 km. She drives a VW Golf with a real-world consumption of 7.2 L/100km and the current fuel price is €1.78/liter. It is a round trip.
Calculation: (585 × 2) × (7.2 ÷ 100) × €1.78 = 1,170 km × 0.072 × €1.78 = €150.04 for the full round trip (about 84.3 liters of fuel). One-way cost: €75.02.
She also calculates that at 120 km/h instead of 100 km/h, consumption rises to ~8.5 L/100km — adding €21 to the round trip. She decides to stick to 100 km/h and save the money for dinner.
James commutes 28 miles each way to work, 5 days a week. His Toyota Camry averages 32 MPG and gasoline costs $3.45/gallon in his city.
Weekly calculation: (28 × 2 × 5) ÷ 32 × $3.45 = 280 ÷ 32 × $3.45 = 8.75 gallons × $3.45 = $30.19/week. Over 50 working weeks that is $1,509/year just for the commute.
He realizes that carpooling 2 days a week would save over $600 annually — and considers whether a hybrid (48 MPG) would cut his annual fuel bill by $500 compared to his current car.
The Santos family plans a camping trip: 420 km to the campsite, visiting two spots along the way (total estimated driving: 1,100 km). Their 7-seater SUV uses 10.5 L/100km loaded with luggage and five passengers. Diesel costs $1.55/liter.
Total fuel: 1,100 × (10.5 ÷ 100) = 115.5 liters. Cost: 115.5 × $1.55 = $179.03. They budget $200 for fuel (10% contingency) and set aside the rest for campsite fees.
There are three reliable ways to determine your vehicle's real fuel consumption:
In metric: multiply distance (km) by your fuel consumption (L/100km), divide by 100, then multiply by the price per liter. In imperial: divide distance (miles) by your MPG, then multiply by the price per gallon. Our calculator does this automatically — just enter the three values and hit Calculate.
Fuel efficiency measures how far your car travels per unit of fuel. In metric countries it's L/100km (lower = better). In the US and UK it's MPG (higher = better). Check your dashboard's trip computer, the owner's manual, or the manufacturer's website. Real-world efficiency is typically 10–15% lower than official specs.
Use the formula: MPG (US) = 235.21 ÷ L/100km. For example, 7 L/100km ≈ 33.6 MPG. To go the other way: L/100km = 235.21 ÷ MPG. Our calculator handles both units — simply select the appropriate mode.
Yes, significantly. Most cars peak in efficiency at 80–100 km/h (50–65 mph). Above that, aerodynamic drag increases exponentially. Driving at 130 km/h instead of 100 km/h typically increases fuel use by 20–30%, which translates directly to higher trip costs.
Air conditioning typically adds 5–25% to fuel consumption depending on temperature and vehicle. At highway speeds the penalty is around 5–10%. In heavy city traffic on a hot day it can reach 20–25%. Interestingly, at speeds above 80 km/h, closing windows and using AC is usually more fuel-efficient than the drag from open windows.
Cold starts, traffic congestion, under-inflated tyres, carrying excess weight, roof racks, and aggressive driving style all increase real-world consumption above the calculated estimate. Add 10–15% as a contingency buffer when planning fuel budgets for long trips.
Use cruise control on highways to maintain a constant speed. Keep tyre pressure correct. Remove unnecessary weight and roof racks. Plan the route to avoid traffic. Accelerate and brake smoothly. A well-maintained car (clean air filter, fresh oil) also runs more efficiently.
Yes — the round trip calculation simply doubles the one-way distance before applying the fuel formula. In practice return journeys may vary slightly due to traffic or route changes, but for planning purposes double the one-way estimate is accurate and gives a useful upper bound.
Use GasBuddy (US/Canada), Petrolprices.com (UK), or Clever Tanken (Germany) for live crowd-sourced prices. Alternatively, note the price board at your nearest station before departure. Prices can vary 10–15% between the cheapest and most expensive stations in the same city.