How to Use the Fuel Cost Calculator

Enter the distance of your trip, your vehicle’s fuel consumption and the current fuel price in cents per litre.

You can also select a return trip, enter multiple trips, split the cost between passengers and add other expenses such as tolls or parking.

The calculator estimates:

• Total distance travelled;
• Total litres of fuel required;
• Total fuel cost;
• Total trip cost including optional extras;
• Fuel cost per kilometre;
• Fuel cost per 100 kilometres;
• Trip cost per person; and
• An annual commuting fuel estimate.

How Is Fuel Cost Calculated?

For vehicles rated in litres per 100 kilometres, the first step is to calculate the amount of fuel required.

Because Australian fuel prices are commonly displayed in cents per litre, the calculator converts the entered cents into dollars before calculating the total cost.

Fuel Cost Example

What Does L/100 km Mean?

Litres per 100 kilometres, written as L/100 km, is a common measure of vehicle fuel consumption in Australia.

A car rated at 8 L/100 km is estimated to use approximately eight litres of fuel to travel 100 kilometres under the conditions represented by that consumption figure.

A lower L/100 km figure generally means the vehicle uses less fuel.

How Do I Find My Car’s Fuel Consumption?

You may find a fuel-consumption figure in:

• The vehicle specification sheet;
• The owner’s manual;
• The vehicle’s trip computer;
• A manufacturer website; or
• Your own fuel-use records.

Real-world fuel consumption can differ from an official figure because of driving conditions and vehicle usage.

How to Calculate Your Actual Fuel Consumption

A practical way to estimate real-world fuel efficiency is to record how much fuel is used between two full tanks.

For example, if your vehicle uses 45 litres over 600 km:

45 ÷ 600 × 100 = 7.5 L/100 km

How Much Does Fuel Cost Per Kilometre?

Fuel cost per kilometre is calculated by dividing total fuel cost by the distance travelled.

For example, if fuel costs $30 for a 200 km trip:

$30 ÷ 200 = $0.15 per km

How Much Does Fuel Cost Per 100 km?

If your vehicle uses 8 litres per 100 km and fuel costs $1.90 per litre:

This can be a useful figure for comparing running costs between vehicles.

One-Way vs Return Trip Fuel Cost

A return journey usually doubles the one-way distance.

For example, if your destination is 150 km away:

• One-way distance = 150 km;
• Return distance = 300 km.

The calculator automatically doubles the distance when Return trip is selected.

How to Split Fuel Costs Between Passengers

If several people are sharing the trip cost, the calculator divides the total trip cost by the number of passengers entered.

You can include tolls and parking in the extra-cost field before splitting the total.

Fuel Costs for Daily Commuting

Small daily fuel costs can add up over a full working year.

The annual commuting estimate uses:

This can help estimate how much commuting by car may cost over a year.

What Affects Real-World Fuel Consumption?

Actual fuel use can differ considerably from a vehicle’s advertised figure.

Factors can include:

• Traffic congestion;
• Stop-start driving;
• Highway versus city driving;
• Vehicle speed;
• Air-conditioning use;
• Tyre pressure;
• Vehicle load;
• Towing;
• Driving style;
• Road gradient;
• Weather; and
• Vehicle condition.

City vs Highway Fuel Consumption

Many vehicles use more fuel in urban stop-start traffic than during steady highway driving.

If you regularly drive in mixed conditions, using your own historical average L/100 km can produce a more practical estimate than relying only on a laboratory-rated fuel figure.

Petrol vs Diesel Fuel Cost

The calculator works for both petrol and diesel vehicles because you enter the actual fuel price and consumption rate yourself.

For example, a diesel vehicle may have a different fuel consumption rate and a different cents-per-litre price from a petrol vehicle.

Simply enter the appropriate figures for the vehicle being compared.

Can I Use This for Premium Petrol?

Yes. Enter the current cents-per-litre price for the fuel grade you use, such as regular unleaded, premium unleaded or diesel.

Does This Calculator Include Tolls and Parking?

Yes. The optional Other trip costs field can be used for expenses such as:

• Tolls;
• Parking;
• Ferry charges; or
• Other fixed trip expenses.

These costs are added to the calculated fuel cost to provide a broader trip-cost estimate.

Does Fuel Cost Equal the Full Cost of Driving?

No. Fuel is only one component of the cost of operating a vehicle.

Other vehicle costs may include:

• Registration;
• Insurance;
• Servicing;
• Tyres;
• Repairs;
• Depreciation;
• Loan interest;
• Parking; and
• Tolls.

How Fuel Price Changes Affect Trip Cost

The total cost of a trip changes directly with the fuel price when all other assumptions remain the same.

For example, if your car needs 20 litres for a trip:

• At $1.70/L, fuel costs $34;
• At $1.90/L, fuel costs $38;
• At $2.10/L, fuel costs $42.

The fuel-price comparison table above lets you see this effect quickly.

Fuel Cost Calculator Assumptions

This calculator assumes:

• The entered fuel-consumption rate remains constant;
• The entered fuel price remains constant for the trip;
• The vehicle uses the same fuel type throughout the calculation;
• No idling fuel is separately added;
• No change in fuel efficiency due to towing or load is automatically calculated;
• Other costs are added as a single total amount;
• Annual commuting uses the same daily travel pattern; and
• Results are estimates rather than exact vehicle operating costs.

Related Australian Calculators