Oil Barrels to US Cups (bbl to cup)

1 oil barrel equals 672 US cups exactly.

1 oil barrel = 672 US cups

How to convert oil barrels to US cups

To convert oil barrels to US cups, multiply the number of oil barrels by 672. This factor is exact. To go the other way, multiply US cups by 0.001488095238 (rounded).

US cups = oil barrels × 672

Example: 10 oil barrels = 6,720 US cups.

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 Cup (cup)

US customaryCurrent unit

One sixteenth of a US gallon, 236.588 mL (8 US fluid ounces). The standard US recipe cup.

Cups began as household drinking vessels, not scientific units, which is why they remain the messiest measures in the kitchen. The US customary cup was defined by slicing up the gallon: half a pint, or eight US fluid ounces, about 236.6 milliliters. Unlike the larger units, nobody ever fixed it to a physical vessel, so it exists only as a fraction of the gallon.

The customary cup is not the only American cup. For nutrition labels, US regulation defines a cup as exactly 240 milliliters, a rounder figure that sits slightly above the customary size. Packaged foods therefore list a serving in the legal cup while a measuring cup from the hardware store follows the customary definition. The gap is 3.4 milliliters, which hardly matters for soup but can matter in baking. Cup measures also hide the weight of dry ingredients, since a cup of sifted flour and a cup of packed flour differ substantially, which is why much of the world prefers grams.

1 US cup = 0.2365882365 liters (exactly).

Sources: Wikipedia: Cup (unit); NIST SP 811, Appendix B.8: conversion factors for volume; 21 CFR 101.9: nutrition labeling household measures

Related conversions

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