Fuel Cost Calculator

How to calculate fuel cost

1. For a trip, enter the total distance you plan to drive, including the return journey if needed.
2. Enter your vehicle's known average fuel consumption or economy. Select L/100 km, km/L, US MPG or Imperial MPG to match it.
3. Enter the pump price in the selected currency and choose whether it is per litre, US liquid gallon or Imperial gallon.
4. For fuel you already know the volume of, switch to “A known fuel amount” and enter that volume instead. Read the cost, open the calculation details if useful, or copy the result.

What this fuel cost calculator supports

• Trip cost from distance, known fuel economy and an entered fuel price.
• Cost of a known fuel amount, with no distance or economy required.
• Kilometres, miles, L/100 km, km/L and explicitly separate US and Imperial MPG.
• Independent fuel-volume and price-volume units, with up to four decimal places in pump prices.
• One cost in a selected currency, with a copyable summary and optional calculation details.

When it is useful

• Budgeting the fuel portion of a road trip when you already know the route distance.
• Checking a fuel-cost estimate from a familiar average consumption figure.
• Pricing a known quantity of petrol or diesel at a rate you enter.
• Working with fuel economy and pump prices expressed in different volume units.

Understanding distance, economy and fuel price

With L/100 km, fuel in litres equals distance in kilometres multiplied by consumption and divided by 100. With km/L, divide distance in kilometres by the economy figure. With MPG, divide distance in miles by the matching MPG figure to obtain that kind of gallon.

Convert the calculated fuel amount to the unit used by the price, then multiply it by the price per unit. The calculator keeps those conversions and the entered pump rate unrounded; it rounds the final cost only once.

US and Imperial gallons are different volumes. One US liquid gallon is exactly 3.785411784 litres; one Imperial gallon is exactly 4.54609 litres. Select the economy's gallon definition from its source, then select the pump-price unit independently. They may use different gallon definitions.

Enter prices in the main unit of the chosen currency. For example, 145.9 pence per litre means GBP 1.459 per litre, not GBP 145.9. Prices may have more decimal places than a final payable amount.

Changing a unit or currency keeps the entered number and changes how it is interpreted. It does not convert the draft or apply an exchange rate. Re-enter the matching value if you intended a physical or currency conversion.

Final costs use the selected currency's standard decimal precision. A positive cost below its smallest unit is shown as less than that unit, not as zero. An explicitly entered zero price does give zero cost.

A full-trip estimate uses one average economy figure and one fuel price. Real consumption and the prices you encounter may differ, so treat the result as a budget estimate rather than a guaranteed bill.

Fuel cost examples

A 500 km trip at 7 L/100 km needs 35 litres. At EUR 1.80 per litre, its estimated fuel cost is EUR 63.00.

A 300 mile trip at 30 US MPG needs 10 US liquid gallons. At USD 4.00 per US gallon, its estimated fuel cost is USD 40.00.

A 300 mile trip at 30 Imperial MPG needs 10 Imperial gallons, equal to 45.4609 litres. At GBP 1.50 per litre, the unrounded cost is GBP 68.19135, shown as GBP 68.19.

For a known fuel amount, 35 litres at EUR 1.80 per litre costs EUR 63.00. Distance and economy are not needed for this calculation.

What the result does not include

The calculator does not find routes, traffic conditions, live pump prices, vehicle specifications or exchange rates. Enter figures that belong to your own planned trip.

Fuel cost is not total journey cost. Tolls, parking, rental charges, wear, insurance and other fees are not included.

Use liquid-fuel consumption, not MPGe or electrical energy consumption. This tool does not estimate the complete fuel-and-electricity cost of a plug-in hybrid.

It does not decide whether a tankful will reach your destination or where it is safe to refuel. It also does not predict taxes, refunds, reimbursements or shared-cost settlements.

Your inputs and privacy

Calculations happen locally in your browser. The calculator does not upload your figures to obtain prices, routes or vehicle information.

Your result is copied only when you choose Copy result. The page does not put your inputs into a share URL or save a trip history. Normal site consent and privacy controls still apply.