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Fuel Cost Calculator

Use this fuel cost calculator to estimate how much you will spend on fuel for a single trip or a regular commute based on distance, vehicle fuel consumption, and pump price.

You can also enter the number of passengers to see the cost per person immediately, which is useful for carpooling, shared trips, or ride-sharing platforms.

The tool is designed for drivers, fleet managers, and planners who need a quick, transparent way to forecast fuel expenses, compare vehicle options, and evaluate whether a trip is more convenient by car, public transport, or alternative powertrain.

Updated Dec 1, 2025

Results

Fuel used

6.5

Trip fuel cost

$11.70

Cost per passenger

$11.70

Methodology

The calculator assumes that fuel consumption is expressed in litres per 100 kilometres (L/100 km), the standard metric used on many official fuel economy labels and in WLTP and EPA test cycles.

First, fuel used is computed as: fuel used in litres = distance in kilometres × (fuel consumption in litres per 100 kilometres ÷ 100).

Next, total fuel cost is obtained by multiplying the fuel used by the fuel price per litre entered by the user: total cost = distance_km × fuel_consumption_l_per_100km ÷ 100 × fuel_price_per_liter.

If you enable split cost by entering more than one passenger, the calculator divides the total cost by the number of occupants: cost per passenger = total cost ÷ number of passengers.

For the most reliable results, use fuel consumption values based on long-term averages or official EPA or WLTP ratings for your specific vehicle model, and distances measured with a reliable odometer or mapping software.

Real-world fuel consumption can differ significantly from laboratory ratings because of driving style, average speed, traffic conditions, payload, tyre pressure, road gradient, temperature, and the use of air conditioning or heating.

Typical factors that increase fuel use include frequent hard acceleration and braking, high cruising speeds, under-inflated tyres, carrying unnecessary weight, roof racks or boxes, short cold-start trips, and stop-and-go urban traffic.

Worked examples

Example 1 – Solo commuter: A 50 km round-trip commute with a car that averages 6.5 L/100 km and a fuel price of 1.80 per litre uses about 3.25 litres and costs roughly 5.85 for the day.

Example 2 – Trip shared with friends: A 300 km weekend trip with the same car and fuel price uses about 19.5 litres and costs about 35.10 in total. With four passengers in the car, the cost per passenger is about 8.78.

Example 3 – Cost per 100 km by powertrain (indicative values): petrol car at 7.0 L/100 km and 1.80 per litre ≈ 12.60 per 100 km; diesel car at 5.5 L/100 km and 1.70 per litre ≈ 9.35 per 100 km; battery electric vehicle at 17 kWh/100 km and 0.25 per kWh ≈ 4.25 per 100 km. These values are illustrative only and depend on specific vehicles and local energy prices.

Further resources

Expert Q&A

What formula does this fuel cost calculator use?

Fuel used is calculated as distance in kilometres multiplied by fuel consumption in litres per 100 kilometres divided by 100. Total fuel cost is then fuel used multiplied by the fuel price per litre: cost = distance_km × fuel_consumption_l_per_100km ÷ 100 × fuel_price_per_liter. If you enter more than one passenger, the cost per passenger is total cost divided by the number of passengers.

How should I choose a realistic fuel consumption value?

You can use official values from EPA or WLTP fuel economy labels for your vehicle or, even better, calculate a long-term average from your own driving by dividing fuel added at the pump by distance travelled between fill-ups. Real-world values are often higher than laboratory ratings, especially in urban driving or at very high motorway speeds.

How accurate are fuel cost estimates compared with real-world driving?

The estimate is as accurate as the inputs. If you use a realistic fuel consumption figure and a distance measured with a reliable odometer or mapping tool, the cost estimate is typically within a few percent. Short trips, aggressive driving, heavy loads, steep gradients, or severe weather can all increase fuel use compared with official test-cycle values.

What does the number of passengers field do?

The number of passengers field does not change the total fuel cost estimate. It simply divides the total trip cost equally among the occupants so you can see a fair per-person cost for carpooling, ride-sharing, or splitting expenses on a road trip.

Can I compare petrol, diesel, and electric vehicles with this tool?

Yes. For petrol or diesel cars, use fuel consumption in L/100 km and the fuel price per litre. For electric vehicles, you can convert energy consumption from kWh/100 km into an equivalent cost by multiplying by your electricity price per kWh. The examples below the calculator show indicative costs per 100 km for different powertrains.

Where can I find trustworthy fuel consumption and efficiency data?

Official fuel economy values are published by agencies such as the U.S. Department of Energy and Environmental Protection Agency on fueleconomy.gov, by European authorities using WLTP test procedures, and by national transport or environment agencies. Universities and engineering institutes also publish independent studies on vehicle efficiency and real-world deviations from laboratory tests.

Sources & citations