Oil Barrels to US Gallons (bbl to gal)

1 oil barrel equals 42 US gallons exactly.

1 oil barrel = 42 US gallons

How to convert oil barrels to US gallons

To convert oil barrels to US gallons, multiply the number of oil barrels by 42. This factor is exact. To go the other way, multiply US gallons by 0.02380952381 (rounded).

US gallons = oil barrels × 42

Example: 10 oil barrels = 420 US gallons.

Pints, quarts, gallons and fluid ounces differ between the US and the UK. Units are labeled 'US' or 'imperial' to avoid confusion.

About these units

Oil Barrel (bbl)

US customaryCurrent unit

Exactly 42 US gallons (158.987 L). The unit of crude oil trade since the 1860s Pennsylvania oil fields.

The oil barrel did not come from the oil industry's own design but from the barrels already lying around Pennsylvania. After Drake's well of 1859 started a boom, producers shipped crude in whatever containers were handy: whiskey barrels of around 40 gallons, plus 42 and 45 gallon casks. Buyers grew suspicious of the inconsistency, and around 1866 producers settled on the wine tierce of 42 gallons, two gallons bigger than the common whiskey barrel. An Oil City circular of August 1866 also promised an allowance of two gallons in every 40.

By 1872 the 42-gallon standard was firmly established, and US government bodies adopted it in 1882. The barrel is exactly 42 US gallons, about 159 liters, and remains the worldwide pricing unit for crude, even though many countries report volumes in cubic meters. EIA says Strait of Hormuz flows of 20 million barrels a day equal about a fifth of global consumption, implying roughly 100 million barrels a day. The abbreviation bbl has a disputed origin: a popular story links it to Standard Oil's blue barrels, but the abbreviation predates the oil industry.

1 oil barrel = 158.9872949 liters (approximately).

Sources: Wikipedia: Barrel (unit); NIST SP 811, Appendix B.8: conversion factors for volume; EIA: Today in Energy, Strait of Hormuz oil flows

US Gallon (gal)

US customaryCurrent unit

Exactly 231 cubic inches or 3.785411784 liters (128 US fluid ounces). About 17% smaller than the imperial gallon.

The US gallon is a survivor of English wine trade. Around 1706, a statute in Queen Anne's reign fixed the wine gallon at exactly 231 cubic inches, settling confusion among the competing gallons for wine, ale and corn. British colonies in North America used that wine gallon, and in 1824 Britain replaced all its gallons with a new imperial one while the United States kept the old measure. It was adopted as the legal US standard in 1836 and is still defined as exactly 231 cubic inches, or 3.785411784 liters.

That makes the US gallon about 17 percent smaller than the imperial gallon, a difference that explains why American and British fuel-economy figures cannot be compared directly. Everyday uses are milk jugs, paint cans and gasoline pumps. One gallon divides evenly into four quarts, eight pints, sixteen cups and 128 fluid ounces. A gallon of water weighs a little over 8 pounds, an easy figure to remember when loading a car with water jugs.

1 US gallon = 3.785411784 liters (exactly).

Sources: Wikipedia: Gallon; NIST SP 811, Appendix B.8: conversion factors for volume

Related conversions

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