km/L to L/100km Converter
Convert kilometres per litre to litres per 100 km. Results update as you type; exact factors shown.
One kilometres per litre is 100 litres per 100 km — see the exact factor, not a rounded rule of thumb.
How the km/l to l/100km converter works
Fuel economy is an inverse quantity: lower L/100 km is better, higher mpg is better. mpg (US) = 235.215 / (L/100 km) because a US gallon is 3.785 L and a mile 1.609 km; mpg (UK) = 282.481 / (L/100 km) with the 4.546 L imperial gallon. UK mpg figures are therefore always 20% higher than US mpg for the same car.
Australia is fully metric under the National Measurement Act 1960; imperial units appear only in trade with the US and in older documents.
Common fuel economy conversions
| From | To | Units |
|---|---|---|
| 5 km/L | 20 L/100 km | kilometres per litre to litres per 100 km |
| 8 km/L | 12.5 L/100 km | kilometres per litre to litres per 100 km |
| 10 km/L | 10 L/100 km | kilometres per litre to litres per 100 km |
| 12 km/L | 8.3333 L/100 km | kilometres per litre to litres per 100 km |
| 14 km/L | 7.1429 L/100 km | kilometres per litre to litres per 100 km |
| 16 km/L | 6.25 L/100 km | kilometres per litre to litres per 100 km |
| 18 km/L | 5.5556 L/100 km | kilometres per litre to litres per 100 km |
| 20 km/L | 5 L/100 km | kilometres per litre to litres per 100 km |
| 25 km/L | 4 L/100 km | kilometres per litre to litres per 100 km |
| 30 km/L | 3.3333 L/100 km | kilometres per litre to litres per 100 km |
| 40 km/L | 2.5 L/100 km | kilometres per litre to litres per 100 km |
| 50 km/L | 2 L/100 km | kilometres per litre to litres per 100 km |
Units in this converter and their exact factors
| Unit | Symbol | To L/100 km |
|---|---|---|
| litres per 100 km | L/100 km | x |
| kilometres per litre | km/L | 100÷x |
| miles per imperial gallon | mpg (UK) | 282.480936÷x |
| miles per US gallon | mpg (US) | 235.214583÷x |
FAQFrequently asked questions about fuel economy conversion
How do I convert km/L to L/100km?
Divide 100 by the figure. 20 km/L is 5 L/100km.
What is a good km/L?
Over 18 km/L is efficient for a petrol car; hybrids exceed 25.
Why does Australia use L/100km?
Because fuel used per distance scales linearly with cost, which km/L does not.
What is 12 km/L in L/100km?
8.33 L/100km.
Which is easier to compare?
L/100km, because the difference between 6 and 7 means the same everywhere on the scale.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Measurement Institute (NMI) — Australia's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.