The API Gravity Calculator helps to determine the Corrected API at 60 Deg F for Jet A, Diesel and Gasoline. Additionally the app calculate the weight of gas. 

*The American Petroleum Institute gravity, or API gravity, is a measure of how heavy or light a petroleum liquid is compared to water: if its API gravity is greater than 10, it is lighter and floats on water; if less than 10, it is heavier and sinks.