MMbbl

MMbbl is a unit of volume used in the oil and gas industry to quantify crude oil and condensates. It stands for million barrels, with one MMbbl equal to 1,000,000 barrels. A single barrel is defined as 42 US gallons, or about 159 liters, and therefore 1 MMbbl is roughly 158,987 cubic meters.

The notation arises from Roman numerals, where M represents 1,000 and MM signifies 1,000,000. In practice, capitalization conventions can vary by source; some documents use Mbbl to denote thousand barrels and MMbbl for million barrels, while others may differ. Despite these variations, MMbbl is widely understood in the energy sector to mean millions of barrels.

MMbbl is commonly used to describe aggregate volumes such as proved reserves, cumulative production, and life-of-field or project estimates. It is a static volume measure, not a rate. For production rates, per-day forms such as Mbbl/d or MMbbl/d are used (thousand or million barrels per day, respectively).

Examples and context: a field with 2 MMbbl of proved reserves contains about two million barrels of oil. Financial and technical reports may present reserves and production in MMbbl to facilitate comparison across fields and countries with large-scale outputs.

See also: barrels, oil reserves, crude oil, production rates.