AutoTools

15 mpg to L/100 km

15 mpg is 15.68 L/100 km when the figure is measured in US gallons, or 18.83 L/100 km in imperial gallons. Which one applies depends entirely on where the number came from — a US window sticker and a UK brochure use the same two letters for different volumes.

L/100 km (US)
15.68
from 15 mpg US
L/100 km (imperial)
18.83
from 15 mpg imp
km/L
6.38
US basis
mpg imperial
18.0
same car as 15 mpg US

The working

US:        235.21 ÷ 15 = 15.68 L/100 km
imperial:  282.48 ÷ 15 = 18.83 L/100 km

where 235.21 = 100 × 3.785411784 ÷ 1.609344
      282.48 = 100 × 4.54609    ÷ 1.609344

Nearby figures

Questions

What is 15 mpg in L/100 km?

15 mpg is 15.68 L/100 km if the figure is US, or 18.83 L/100 km if it is imperial. Divide 235.21 by the mpg for US gallons, or 282.48 for imperial.

Is 15 mpg good?

It is thirsty by current standards. 15.7 L/100 km is typical of larger SUVs, pickups and older or performance cars.

What is 15 US mpg in UK mpg?

About 18 mpg imperial. The imperial gallon is 20% larger, so the same car always scores higher on the UK scale — which is why the two are not interchangeable.

Want the running cost rather than the conversion? Open the fuel cost calculator.