Fuel Consumption Converter

Translate fuel economy between US MPG, UK MPG, L/100km, and km/L in one step.

Convert fuel economy instantly. Free MPG, L/100km, km/L converter comparing US, UK and metric consumption figures.

About MPG / L/100km

Translate fuel economy between US MPG, UK MPG, L/100km, and km/L in one step.

Fuel economy inverts awkwardly: MPG is distance-per-fuel while L/100km is fuel-per-distance, so bigger is better in one and worse in the other. This tool pivots through L/100km to show all four figures at once — including the US/UK gallon trap (an imperial gallon is ~20% larger, inflating UK MPG).

Remember ratings are lab figures; real driving typically lands 10–20% worse. Everything runs in your browser.

Where it is used

Reading foreign car reviews, comparing imports, converting fleet specs, and settling MPG arguments.

How to use the MPG / L/100km

  1. Value — enter the value (e.g. 30).
  2. From — enter the value.
  3. Calculate — press the Calculate button to see the result instantly above.

Formula

Pivot on L/100km: US MPG = 235.214/L, UK MPG = 282.481/L, km/L = 100/L.

Examples

Example

value:30
from:mpg-us
Result: 30 US MPG = 7.84 L/100km = 36.03 UK MPG

Frequently Asked Questions

Why do UK MPG figures look better?
The imperial gallon (4.546 L) is bigger than the US gallon (3.785 L). Same car, same driving: the UK number reads ~20% higher.
MPG or L/100km — which is more honest?
L/100km. MPG hides absolute savings: improving 10→20 MPG saves far more fuel than 30→40, but MPG gaps look equal. L/100km scales linearly with cost.
How do I convert to km per liter?
Divide 100 by the L/100km figure. 7.84 L/100km ≈ 12.76 km/L.
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