Keep distance, economy and fuel-price units consistent when budgeting a journey.
Use the Fuel Cost Calculator alongside this illustrative example.
A practical example
For a 300 km trip at 6 L/100 km, estimated fuel use is 18 L. At an illustrative price of 1.50 per litre, fuel cost is 27.00. A return trip covering the same distance doubles that to 54.00 before changes in traffic or load.
Check the result
Compare the calculation with your own recent consumption rather than relying only on a brochure figure. If using MPG, check whether the source means US or imperial gallons and match the fuel-price unit.
Try a comparison
Increase the example economy from 6 to 7 L/100 km while keeping distance and price fixed. Fuel use becomes 21 L and cost 31.50. A larger L/100 km value means more fuel consumed, even though larger MPG values mean better economy.
What this does not establish
Tolls, parking and vehicle wear are not fuel costs. Add them separately when comparing a drive with another travel option.
Try the tools from this guide
Keep reading
How to Estimate Travel Time from Distance and Speed
Estimate travel time from an average speed rather than a speed limit.
How to Convert MPG and Litres per 100 Kilometres
Identify which gallon a quoted MPG figure uses before comparing vehicles.
How to Calculate Mileage Reimbursement Correctly
Keep an expense claim tied to recorded eligible distance and the applicable rate.