Work out your real fuel economy — MPG or L/100km — and see exactly what each mile and each trip costs you.
1. Fill the tank completely and reset your trip odometer.
2. Drive normally — city, highway, whatever your routine is.
3. Fill up again at the same pump if possible, and note the gallons added.
4. Divide the trip miles by those gallons: 320 miles ÷ 12 gallons = 26.7 MPG.
Use the optional second trip field to combine two fill-ups — that smooths out variations from hilly routes, traffic and temperature, giving you a more honest average.
20 MPG ≈ 11.8 L/100km — large SUV / truck
25 MPG ≈ 9.4 L/100km — midsize SUV
30 MPG ≈ 7.8 L/100km — typical sedan
40 MPG ≈ 5.9 L/100km — compact car
50 MPG ≈ 4.7 L/100km — hybrid