Categories🚗 Auto & TransportFuel Cost Calculator

Fuel Cost Calculator

Calculate fuel expenses for trips using US MPG, Imperial MPG, or L/100 km.

Total Fuel Cost
$37.39
Fuel Needed: 10.714 Gallons
Guide & Educational Reference
How to Use the Fuel Cost Calculator
  1. 1Select your preferred Unit System: US MPG (Miles & US Gallons), Imperial MPG (Miles & UK Gallons), or Metric (km & L/100 km).
  2. 2Enter the travel distance for your trip.
  3. 3Enter your vehicle fuel efficiency (MPG or L/100 km).
  4. 4Enter the current price of fuel per gallon or per liter.
  5. 5View total fuel cost ($) and total volume of fuel needed.
Understanding Fuel Cost Calculations

Calculating fuel cost helps drivers estimate fuel expenses for road trips, daily commutes, or fleet planning. The calculation computes total fuel consumed based on vehicle fuel efficiency and multiplies it by the unit price of fuel.

Formulas Implemented by THE CALC
1. Fuel Needed (MPG Systems)

Used for US MPG and Imperial MPG modes.

Fuel Needed (gallons) = Distance (miles) / Fuel Efficiency (MPG)
2. Fuel Needed (Metric System)

Used for L/100 km metric mode.

Fuel Needed (liters) = (Distance in km / 100) × Efficiency (L/100 km)
3. Total Fuel Cost

Multiplies required fuel volume by unit fuel price.

Total Fuel Cost ($) = Fuel Needed × Price per Unit
Practical Real-World Example
300-Mile Highway Trip (28 US MPG at $3.49/gallon)
Fuel Needed = 300 / 28 = 10.71 US Gallons Total Fuel Cost = 10.7143 × $3.49 = $37.39
→ Fuel Needed: 10.71 Gallons | Total Fuel Cost: $37.39
300 miles, 30 MPG, $3.60/gallon
Fuel = 300 / 30 = 10 gallons; Cost = 10 × 3.60
→ $36.00 for the trip
500 km at 7 L/100km, $1.80/L
Fuel = (500 / 100) × 7 = 35 L; Cost = 35 × 1.80
→ $63.00 for the trip
Important Driving & Modeling Assumptions
  • Rated vs real-world economy: Official EPA fuel economy ratings assume ideal laboratory conditions. Real-world consumption varies with speed, acceleration, cargo weight, tire pressure, and air conditioning usage.
  • Unit system alignment: Ensure fuel price matches the selected system (price per US gallon for US MPG, price per UK gallon for Imperial MPG, or price per liter for L/100 km).
  • Scope exclusion: This calculator estimates fuel cost only. Toll fees, parking charges, vehicle maintenance, and depreciation are not included.
Frequently Asked Questions

How does L/100 km differ from MPG?

MPG measures how far you can drive on one gallon of fuel (higher is better). L/100 km measures how many liters of fuel are consumed to travel 100 kilometers (lower is better).

Is an Imperial Gallon larger than a US Gallon?

Yes. An Imperial (UK) Gallon is approximately 4.546 liters, whereas a US Gallon is approximately 3.785 liters (1 Imperial Gallon ≈ 1.201 US Gallons).

How does the L/100 km mode differ from the MPG mode?

In MPG mode fuel used = distance ÷ efficiency. In L/100 km mode fuel used = (distance ÷ 100) × efficiency. The cost is fuel used × price per unit either way.

What inputs are required?

Distance, efficiency, and fuel price must all be greater than zero, or the calculator returns no result.

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