Physics & Engineering
Fuel Economy (MPG & L/100km)
From distance and fuel used.
Educational estimates only. Not medical, legal, tax, or financial advice.
Guide: Fuel Economy (MPG & L/100km)
What it does
Computes MPG and converts to metric fuel consumption.
How to use it
Enter miles driven and US gallons used.
Formula
MPG = miles ÷ gallons; L/100km ≈ 235.214583 ÷ MPG (US).
Example
300 miles on 10 gal → 30 MPG.
FAQs
US vs imperial gallons?
This tool assumes US gallons unless labeled otherwise.
Trip vs tank?
Use odometer distance and fuel actually pumped for best accuracy.
Electric vehicles?
MPGe uses different energy content; this page targets liquid fuel MPG.