Convert Barrel (Oil) (bbl (oil)) to Barrel (US) (bbl (US)) instantly.
About these units
Barrel (Oil) (bbl (oil))
An oil barrel is defined as 42 US gallons, or 158.987 liters, and is a fundamental unit in the petroleum industry. This peculiar size traces back to the early Pennsylvania oil fields, where producers standardized whiskey barrels and modified wooden casks for oil transport. The need for consistent trade volumes cemented the 42-gallon barrel as the industry norm. Today, global oil production, pricing, and consumption are expressed in barrels—from daily OPEC reports to energy market forecasts. Even though oil is no longer physically shipped in barrels, the unit remains deeply embedded in international energy economics.
Barrel (US) (bbl (US))
The US barrel is a unit with multiple definitions depending on the industry, though the most common general-purpose US barrel is 31.5 US gallons, used historically for dry goods, ale, and various agricultural products. In practice, the US barrel arose from traditional cask-making, where wooden barrels of different shapes were used for storage and transport. Because their capacity varied widely, different industries standardized the barrel at different volumes. Over time, manufacturers and commercial sectors adopted specific barrel sizes for consistency. Today, the US barrel appears in brewing, winemaking, certain agricultural commodities, and historical documents describing early American commerce. Its varied legacy makes it a fascinating example of an evolving unit shaped by economic necessity and craftsmanship.