The oil barrel equals 158.987 litres or 42 US gallons. It is the global pricing unit for crude oil and petroleum products. The US dry barrel (115.6 L) and UK beer barrel (163.7 L) are different units that share the same name.
Real-world: Brent crude and WTI oil are priced in US dollars per barrel. Global oil demand is about 100 million barrels per day.
Read full barrel reference →The litre is the metric volume unit most used in everyday life. It equals 1 cubic decimetre (0.001 m³) or 1000 ml exactly. Bottled water, petrol, milk and household chemicals are all sold by the litre throughout Europe, Africa and Asia.
Real-world: A standard European petrol-car fuel tank is 50–60 L. A 2.0 L engine has a 2 litre displacement. A typical home boiler holds 150 L of hot water.
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