Fuel Cost Calculator
Calculate the fuel cost of a trip, estimate your monthly driving budget or compare two vehicles using the fuel economy and units you already know.
Plan your trip
Enter your journey and vehicle details.
Your estimate will appear here
Enter your journey details to calculate fuel or electricity costs and compare vehicle energy spending.
Results estimate energy costs only. They do not include vehicle purchase price, finance, insurance, servicing, depreciation, registration or tyres. Real fuel and electricity consumption can also vary with traffic, temperature, charging losses, speed, load and driving style.
Get practical context around your estimated fuel or electricity spending and potential savings.
How to Calculate Fuel Cost
A fuel-cost calculation needs three main pieces of information: the distance you will drive, your vehicle's fuel economy and the price you pay for fuel.
CalcNest converts your selected units internally, so you can use kilometres or miles and enter fuel economy as L/100km, km/L, UK MPG or US MPG.
Example
Distance: 300 km
Fuel economy: 7.5 L/100km
Fuel price: $1.90 per litre
Fuel required = 300 × 7.5 ÷ 100 = 22.5 litres
Fuel cost = 22.5 × $1.90 = $42.75
Fuel Economy Units Explained
Different countries describe fuel economy differently. The calculator lets you use the figure you already know rather than converting it manually first.
Trip Cost vs Monthly Fuel Cost
Trip mode is useful for road trips, airport runs, work travel and other individual journeys. Monthly mode is better when the same drive happens regularly, such as commuting to work several times a week.
Using your actual number of journeys and working weeks gives a more useful budget than simply multiplying one trip by 30 days.
Comparing Two Cars
Fuel economy can make a noticeable difference when the same journey is driven repeatedly. The comparison mode holds the journey distance and fuel price constant so the difference is caused by vehicle efficiency rather than different assumptions.
Why Your Real Fuel Cost May Be Different
A calculator is only as accurate as the information entered. Real fuel use can change because of traffic, speed, acceleration, weather, air-conditioning, vehicle load, towing, tyre pressure and mechanical condition.
For the most realistic estimate, use fuel economy measured from your own recent driving rather than relying only on a manufacturer's laboratory figure.
Common Fuel-Cost Example
| Distance | Economy | Fuel Used | At $1.90/L |
|---|---|---|---|
| 50 km | 7 L/100km | 3.5 L | $6.65 |
| 100 km | 7 L/100km | 7 L | $13.30 |
| 250 km | 7 L/100km | 17.5 L | $33.25 |
| 500 km | 7 L/100km | 35 L | $66.50 |