A calculation of the worth of a barrel of crude oil in terms of the value of its refined products, such as gasoline and heating oil. Crack spreads may be based on a variety of refinery models and also depend on the type of crude input. They are usually expressed in dollars and cents per barrel of crude.
To calculate the spread, the cents-per-gallon product prices are multiplied by 42 (the number of gallons per barrel) and subtracted from the crude oil price. For example, when heating oil futures cost $0.60 per gallon and Nymex division light, sweet crude oil is priced at $22 a barrel, the heating oil crack spread in dollars per barrel = $0.60 x 42 = $25.20 – $22 = $3.20.