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Alcohol or Gasoline: Which Is More Cost-Effective?
Enter the price of alcohol and gasoline at the pump to find out the best choice right now.
The 70% rule is used by Brazilian flex-fuel vehicle manufacturers: ethanol is worth it when its price is equal to or less than 70% of the gasoline price. This is because flex engines have about 30% lower efficiency with ethanol in km/L.
Ethanol alcohol price
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Price per liter at the pump today
Gasoline price
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Price per liter at the pump today
Enter the prices to see the recommendation.
The 70% rule is an estimate based on the average performance of Brazilian flex engines. The real result may vary by vehicle model, fuel quality, temperature and driving style. Always compare at the pump.
Rules verified on 2026-09. The 70% threshold may vary by vehicle model and year.
Alcohol vs Gasoline Questions
Why is the threshold 70%?
Because flex engines have about 70% the energy efficiency of gasoline when using ethanol. If alcohol costs more than 70% of the gasoline price, you cover fewer km per dollar spent. Below 70%, alcohol is cheaper per km.
Does the 70% rule apply to any flex car?
It's a good approximation for most Brazilian flex vehicles, but can vary from 68% to 73% depending on the engine, injection technology and vehicle year. Some manufacturers indicate the exact threshold in the owner's manual.
How do I know the alcohol and gasoline price?
Prices vary daily by station and region. Check the station's app, the price board at the entrance, or search on ANP's Preço da Hora (the fuel regulatory agency's price tool).
Does this rule apply to electric cars?
No. Purely electric vehicles don't use liquid fuel. The comparison applies only to flex-fuel vehicles (gasoline + ethanol) or those that accept both.
