Which fuel is cheapest per 100 km?

For a petrol car (or one that runs on E85 / LPG). E85 and LPG are cheaper per litre but you burn more of them: here is the real cost at today’s average prices.

Official prices updated vor 2 Min. Source: data.economie.gouv.fr

FuelAverage priceConsumptionCost per 100 kmMore than the cheapest
E85Cheapest0,898 €/L8,8 L7,86 €—
Autogas1,078 €/L8,4 L9,06 €+ 1,20 €
Super E102,047 €/L7,0 L14,33 €+ 6,47 €
Super E52,117 €/L7,0 L14,82 €+ 6,96 €
Super Plus2,167 €/L7,0 L15,17 €+ 7,31 €

With 25 % extra consumption, E85 beats E10 as long as it costs less than 1,638 €/L (today: 0,898 €/L).

The extra consumption figures are rough (E85: often 20 to 30 %, LPG: 15 to 25 %) and depend on the vehicle. A diesel engine cannot run on petrol, so diesel is not compared here. E85 and LPG need a compatible or converted vehicle.