Automotive
Gas Mileage Calculator
Calculate your car's MPG, L/100km, and trip fuel cost.
Come Usare
Enter the distance you drove, the fuel you used, and the fuel price to compute your vehicle's fuel economy and the cost of the trip.
FAQ
How is MPG calculated?
MPG = Distance (miles) ÷ Fuel Used (gallons). For metric mode, we compute L/100km = (Fuel Used in L ÷ Distance in km) × 100.
What is the difference between MPG and L/100km?
MPG (US/imperial) is distance per fuel unit — higher is better. L/100km (metric) is fuel per fixed distance — lower is better.
How do I estimate trip cost?
Trip Cost = Fuel Used × Fuel Price. Use the cost-per-mile value to project costs across longer distances.
How to Use the Gas Mileage Calculator
Compute your vehicle's MPG (or L/100km) and trip fuel cost based on the distance you drove and the fuel you used.
- Pick a unit system: imperial (miles and gallons) or metric (km and liters).
- Enter the distance you traveled on your trip.
- Enter the fuel you used for that trip.
- Enter the price per gallon (or per liter) for trip cost estimates.
Fuel Economy Formulas
MPG
Higher MPG = better fuel economy.
Example:
Input: 300 miles, 10 gallons
Calculation: 300 ÷ 10
Result: 30 MPG
L/100km
Lower L/100km = better fuel economy.
Example:
Input: 40 liters, 500 km
Calculation: (40 ÷ 500) × 100
Result: 8 L/100km
Trip Cost
Multiply gallons by $/gallon (or liters by $/liter).
Example:
Input: 10 gal × $3.50
Calculation: 10 × 3.50
Result: $35.00
Real-World Use Cases
Road Trips
Plan fuel budgets for long drives.
MPG Tracking
Compare fill-ups to see if your car's efficiency is changing.
Tips
Tips
- Fill up your tank completely to get accurate MPG per tank.
- Cost per mile is a great way to compare commutes or vehicles.