Fuel Cost Calculator — Free Online Tool
Planning a road trip? Enter your distance, your car's fuel efficiency, and the current fuel price to see exactly what the trip will cost — plus cost per mile or kilometer.
What is the Fuel Cost Calculator?
Fuel is often the biggest variable cost of driving, and small differences add up fast on long trips. This calculator works in both systems: mpg (miles per gallon, US-style) and L/100km (metric). Just pick the one on your dashboard or spec sheet.
Beyond trip planning, the per-mile figure is genuinely useful: compare it against rideshare quotes, decide whether driving or flying wins for a weekend trip, or see what that “cheap” SUV really costs to run. Note the estimate covers fuel only — tolls, wear, and depreciation are extra.
How to use this calculator
- Choose MPG or L/100km efficiency units.
- Enter distance, fuel efficiency, and fuel price.
- Click Calculate Fuel Cost for total cost and per-unit cost.
Formula
Frequently asked questions
How do I convert L/100km to mpg?
MPG (US) ≈ 235.2 ÷ L/100km. So 8 L/100km ≈ 29.4 mpg.
Should I use city or highway mileage?
Use a blend matching your trip — mostly highway driving? Use the highway figure.
Does AC affect fuel cost?
Yes — air conditioning can raise consumption 5–25% depending on conditions. Add a buffer for summer trips.
What about electric cars?
Enter your cost per kWh as the 'fuel price' and kWh/100km as efficiency — the math is identical.