Fuel Cost Calculator
The Fuel Cost Calculator estimates how much fuel a trip will cost based on distance, your vehicle's fuel economy, and the local price of fuel. Works in U.S. units (miles, MPG, price per gallon) or metric (kilometers, L/100km, price per liter). Because the calculation assumes one constant fuel-economy figure for the entire trip, entering a combined city/highway MPG or L/100km rating — rather than a highway-only figure — gives the most realistic estimate for typical mixed driving. If you're planning a round trip, remember to enter the full there-and-back distance, since the calculator has no way to know whether the number you type already includes the return leg.
Switch between U.S. Customary and Metric units.
How This Tool Works
Pick your units, then enter your trip distance, your vehicle's fuel economy, and the current price of fuel to calculate the total fuel cost.
Formula & Method
U.S.: gallons needed = distance ÷ MPG, fuel cost = gallons × price per gallon. Metric: liters needed = (distance ÷ 100) × L/100km, fuel cost = liters × price per liter.
Example Calculation
U.S. example: A 450-mile trip in a car averaging 32 MPG, with gas at $3.79/gallon. Gallons needed = 450 ÷ 32 = 14.06 gal. Total fuel cost = 14.06 × $3.79 ≈ $53.30, or about $0.118 per mile. Metric example: A 750 km trip at 7.2 L/100km fuel consumption, with fuel priced at $1.65/liter. Liters needed = (750 ÷ 100) × 7.2 = 54 L. Total fuel cost = 54 × $1.65 = $89.10, or about $0.119 per km.
Frequently Asked Questions
How do I find my car's MPG?+
Check your owner's manual for the EPA-estimated MPG, or use our MPG Calculator to compute your actual real-world fuel economy from a recent fill-up.
Can I calculate fuel cost in liters and kilometers?+
Yes — switch the unit toggle to Metric and enter distance in kilometers, fuel consumption in L/100km, and price per liter. Results are shown in liters and cost per kilometer.
Does this account for highway vs. city driving?+
No, it uses a single fuel-economy value you provide. For more accuracy, use an average that reflects your mix of highway and city driving on the trip.
Should I add a buffer for traffic or detours?+
Yes, if you expect significant traffic or route changes, add 10–15% to your distance estimate to account for extra fuel use from idling and detours.
Does the price I enter already include fuel taxes?+
Yes — enter whatever price is posted at the pump, since that's already the final price including federal, state, and any local fuel taxes. The calculator doesn't add or estimate taxes separately.
How accurate is this for mountain driving, towing, or a heavily loaded vehicle?+
Less accurate than for flat, unloaded driving — the calculator uses a single fuel-economy number for the whole trip, and towing, steep grades, and heavy cargo can all reduce real-world MPG well below your everyday average. Enter a lower MPG (or higher L/100km) figure to reflect those conditions and get a more realistic cost.
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<a href="https://everyfix.net/tools/fuel-cost-calculator/">Fuel Cost Calculator</a> by <a href="https://everyfix.net">EveryFix</a>Related Tools
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