MPG calculator
Work out miles per gallon from a fill-up and convert between MPG, L/100 km and km/L.
- ๐บ๐ธ US federal & state rules
- See sources
Fuel economy
28.6 MPG
8.23 L/100 km
- Liters per 100 km
- 8.23
- Kilometers per liter
- 12.15
- UK MPG (imperial gallon)
- 34.3
- Gallons per 100 miles
- 3.5
U.S. gallons. Converted figures are rounded.
- For an accurate number, fill the tank all the way, reset the trip meter, and divide the miles by the gallons at the next full fill-up.
Show the math
| MPG | 320 miles รท 11.2 gallons = 28.57 |
|---|---|
| L/100 km | 235.215 รท 28.57 = 8.23 |
What to do next
How it works
MPG is miles divided by gallons. To go metric, km per liter = MPG ร 1.609344 รท 3.785412, which is about MPG ร 0.4251, and L/100 km = 100 รท km per liter, or 235.215 รท MPG.
Things to keep in mind
The trip computer in many cars reads a little high. A fill-up to fill-up check over a few tanks gives a more honest number.
MPG and L/100 km run in opposite directions. Going from 10 to 20 MPG saves far more gas per mile than going from 30 to 40, which is why some countries quote fuel use per distance instead.
Sources
Frequently asked questions
How do I calculate my MPG?
Fill the tank, reset the trip meter, drive, then fill up again. Divide the miles driven by the gallons you just pumped: 320 miles on 11.2 gallons is 28.6 MPG.
How do I convert L/100 km to MPG?
Divide 235.215 by the L/100 km figure. A car that uses 8 L/100 km gets about 29.4 MPG.
Why are UK MPG numbers higher?
A UK (imperial) gallon is 4.546 liters and a U.S. gallon is 3.785 liters. The same car rated 30 MPG in the U.S. shows about 36 MPG in the UK.