Fuel Consumption Calculator
Calculate your car's fuel efficiency and cost, or compare ethanol against gasoline.
Two calculators for flex-fuel drivers
The first tab calculates your actual fuel efficiency and cost per kilometer from a fill-up. The second applies the well-known rule of thumb for flex-fuel vehicles: ethanol is worth it when its price is 70% or less of the gasoline price, since ethanol yields roughly 30% less energy per liter.
Calculated instantly, on your device
All math runs directly in your browser as you type — there is no server call and no delay.
Frequently asked questions
Why 70% and not 75%?
The exact break-even ratio depends on the specific engine, but 70% is the most commonly used and conservative rule of thumb for flex-fuel vehicles.
Does this account for engine performance differences?
No, it is a simplified fuel-cost comparison and does not factor in the extra performance some drivers report with ethanol.
Can I use this for a diesel or electric vehicle?
The fuel efficiency tab works for any liquid fuel; the ethanol-vs-gasoline comparison applies only to flex-fuel gasoline vehicles.
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