Calculate how much fuel your trip will cost based on distance and fuel efficiency.
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Total Cost
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Gallons Used
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Cost per Mile
What is a Fuel Cost Calculator?
A fuel cost calculator estimates how much money you'll spend on fuel for a trip, based on the distance, your vehicle's fuel efficiency, and the current fuel price. This is useful for budgeting road trips, comparing vehicles for long-distance driving, and understanding the real cost of commuting.
This tool supports both imperial (miles and MPG) and metric (kilometers and L/100km) units, covering the measurement systems used across North America, Europe, and beyond.
How to Use
1Choose your unit system: Imperial (miles/MPG) or Metric (km/L per 100km).
2Enter your trip distance.
3Enter your vehicle's fuel efficiency (check your car manual or the window sticker).
4Enter the current fuel price per gallon or liter.
5Click Calculate Fuel Cost.
Formula
Imperial (MPG):
Fuel Used (gallons) = Distance (miles) ÷ MPG
Total Cost = Fuel Used × Price per Gallon
Cost per Mile = Total Cost ÷ Distance
Metric (L/100km):
Fuel Used (liters) = Distance (km) × L/100km ÷ 100
Total Cost = Fuel Used × Price per Liter
Cost per km = Total Cost ÷ Distance
Example: 300 miles, 30 MPG, $3.50/gal
Fuel Used = 300 ÷ 30 = 10 gallons
Total Cost = 10 × $3.50 = $35
Cost/mile = $35 ÷ 300 = $0.117
Frequently Asked Questions
Divide your trip distance by your vehicle's fuel efficiency to get fuel used. Multiply by the fuel price to get the total cost. Example: 300 miles ÷ 30 MPG = 10 gallons × $3.50 = $35.
MPG measures how many miles you can drive per gallon — higher is more efficient. L/100km measures how many liters you use per 100 kilometers — lower is more efficient. To convert: L/100km = 235.2 ÷ MPG.
Drive at steady highway speeds (avoid rapid acceleration), keep tires properly inflated, remove unnecessary cargo weight, plan routes to avoid traffic, and keep up with maintenance (air filter, oil, spark plugs).
Yes significantly. Most vehicles are most fuel-efficient between 45–65 mph. Driving at 80 mph can use up to 25% more fuel than at 65 mph. Wind resistance increases exponentially with speed.