Octane and Ethanol Calculator

Octane Studio

In-app purchases

About this app

This calculator provides accurate blending and filling instructions for any gasoline and any ethanol blend to arrive at a desired octane or ethanol percentage. Why bother calculating an ethanol percentage of your fuel blend when you really need to know the octane! The App accommodates any existing fuel blend at any state of fill and provides needed fuel volumes to reach a desired octane or ethanol percentage goal at a desired fill level. Get the precise octane you need for your engine (or perhaps for your particular tune) which will provide the power and safety you demand. The App will even down blend mixtures, allowing you to reduce octane or ethanol to a desired level.

Although there are many Apps, Calculators and websites that provide this capability for an ethanol target, NONE provide it for an octane target, which is the actual meaningful specification for engines and tune requirements. Furthermore, the rare website that claims to offer some basic tables relating octane to ethanol content are simply incorrect and not accurate. This is fundamentally because the resulting octane for a blend depends not only on on the the ethanol % in the ethanol blend but also on the octane and percentage ethanol in the base gasoline. A final significant limitation of other ethanol only blending apps/calculators is a reliance on the name of the ethanol blend having that precise percentage of ethanol, which is almost never the case.

This App is based on actual experimental combustion data taken in a collaboration between Ford Motor Company, GE Energy and BP Products North America. The results were peer reviewed and published by The Society of Automotive Engineers. However, this algorithm is a novel and unpublished capability. It provides complete and unmatched accuracy and flexibility.

Ratings and reviews

Awesome app to quickly figure out e85 blend ratios with gasoline as well as octane with fuel blends.

App requires a $6.99 Subscription before you can even try it out. It may work, but I'm not willing to buy it when there are free apps and websites.

Unique capability that doesn't really exist anywhere to get a precise octane mixture. Tests spot on for Ethanol with my inline sensor. Obviously, can't test for the octane calculations as that takes a special lab and $$$.