How does the 70% rule work?

If the ethanol price is up to 70% of the gasoline price, it is worth fueling with ethanol. Above that, gasoline is more economical.

Is the calculator accurate?

Yes, the calculation considers the difference in efficiency between ethanol and gasoline (ethanol yields about 70% of gasoline).

Yes, the 70% rule is valid for most flex-fuel cars. Newer vehicles may have slightly better efficiency with ethanol.

Find out which fuel is more cost-effective for you

Ethanol Price

Gasoline Price

• The general rule is: if ethanol costs up to 70% of the gasoline price, it's worth it
• This is because ethanol yields on average 70% of what gasoline yields
• Every car is different! Adjust the consumption for a more accurate calculation
• The calculator compares the cost per kilometer driven for each fuel