Fuel Cost Calculator
Estimate trip fuel cost by distance, MPG or L/100km, and gas price — with vehicle comparison
Enter distance, fuel efficiency, and gas price to calculate your trip fuel cost.
What is a Fuel Cost Calculator?
A fuel cost calculator estimates how much you will spend on gas for a trip or over a period of driving. By entering your trip distance, vehicle fuel efficiency (MPG or L/100km), and current gas price, you get an instant cost estimate. It is useful for road trip planning, comparing vehicles, budgeting transportation expenses, and deciding whether to drive or take another form of transport.
How to Use the Fuel Cost Calculator
- Select your unit system (Imperial for MPG/miles, Metric for L/100km)
- Enter the trip distance
- Enter your vehicle's fuel efficiency
- Enter the current gas price per gallon or liter
- Optionally add a second vehicle to compare fuel costs side by side
Features
- Supports both Imperial (MPG/miles/gallons) and Metric (L/100km/liters)
- Shows total fuel used, total cost, and cost per 100 miles or km
- Side-by-side vehicle comparison with savings calculation
- Instant reactive calculation — no submit button needed
Frequently Asked Questions
Where can I find my vehicle's MPG?
Your vehicle's EPA fuel economy rating is on its window sticker and at fueleconomy.gov. Real-world MPG is typically 10–20% lower than EPA estimates due to driving style, traffic, and conditions. Use your actual observed MPG for more accurate results.
How do I convert MPG to L/100km?
To convert MPG to L/100km: divide 235.21 by the MPG value. For example, 30 MPG = 235.21 ÷ 30 = 7.84 L/100km. Lower L/100km means better fuel efficiency, while higher MPG means better efficiency.
How much does it cost to drive 100 miles?
At $3.50/gallon with a 30 MPG vehicle: 100 miles ÷ 30 MPG = 3.33 gallons × $3.50 = $11.67 per 100 miles. A less efficient 20 MPG vehicle costs $17.50 for the same distance — 50% more.