Q: How can I convert from “miles per gallon” to “kilometers per liter?”
A: 1 Kilometer = 0.621371192 miles (1 Mile = 1.6 Kilometers.) 1 Liter = 0.264172051 gallons (4.54 liters = 1 Gallon). Now, using the same formula you used to compute MPG, plug in the metric equivalents. OR, to convert your MPG to KPL, multiply as necessary:
If you get 30 MPG, multiply 30 x 1.6. Now divide that by 4.54. The answer is: 10.57 KPL.
NOTE: Interestingly, people in the metric world tend to compute mileage in “liters per 100 kilometers.”