Exxon Mobil Corporation (NYSE: XOM) or ExxonMobil, is an American multinational oil and gas corporation. It is a direct descendant of John D. Rockefeller's Standard Oil company, and was formed on November 30, 1999, by the merger of Exxon and Mobil. Its headquarters are in Irving, Texas. It is affiliated with Imperial Oil which operates in Canada.

ExxonMobil is one of the largest publicly traded companies by market capitalization in the world and is the largest company in the world by revenue. The company is ranked #3 globally in Fortune Global 500 list in 2011. Exxon Mobil's reserves were 72 billion oil-equivalent barrels at the end of 2007 and, at then (2007) rates of production, are expected to last over 14 years. With 37 oil refineries in 21 countries constituting a combined daily refining capacity of 6.3 million barrels (1,000,000 m³), Exxon Mobil is the largest refiner in the world, a title that was also associated with Standard Oil since its incorporation in 1870.

ExxonMobil is the largest of the six oil supermajors with daily production of 3.921 million BOE (barrels of oil equivalent). In 2008, this was approximately 3% of world production, which is less than several of the largest state-owned petroleum companies. When ranked by oil and gas reserves it is 14th in the world with less than 1% of the total.