Milliliter

A milliliter (symbol ml or mL) is a unit of volume measurement in the metric system. One milliliter is one-thousandth of a liter, equivalent to one cubic centimeter (cm³). Thus 1,000 milliliters equal one liter.

The milliliter is commonly used to measure small volumes in daily contexts: water, milk, fuel samples, liquid medications, and other substances. Because it is smaller than a liter, it allows for precise measurements needed in medical and research work.

Relationship to other units

In the SI system (the international system of units), the base unit of volume is the cubic meter (m³). The liter is an accepted name equal to 0.001 m³, while the milliliter is 0.000001 m³ (one millionth of a cubic meter). Additionally: 1 ml = 1 cm³, 10 ml = 1 centiliter, 100 ml = 1 deciliter.

Measuring equipment

Liquids are measured using graduated cylinders, pipettes, burettes, and test tubes marked with milliliter graduations. When measuring liquid in a glass or transparent vessel, specialists align their eye with the meniscus—the curved surface of the liquid—for an accurate reading.

Medical and household use

Liquid medications, vaccines, and syringes are measured in milliliters. Standard syringes have 0.1 ml graduations, which allow healthcare workers to administer precise doses. In the home, cooking measurements such as spoonfuls are sometimes converted to milliliters; a large spoon is typically about 15 ml and a small spoon about 5 ml, though these measurements may vary from one country to another.