Overview

A quart is a customary unit of measurement used for volume. It is historically defined as one quarter of a gallon and, in common usage, as two pints. For general reference see unit of measurement and the concept of volume. The simple relations—one quart equals one quarter of a gallon and equals two pints—help explain why the quart is convenient in household and commercial contexts: it sits between pints and gallons in scale.

Definitions and common sizes

Because the underlying gallon differs between systems, the quart is not a single universal volume. Typical modern forms are:

  • US liquid quart — used for beverages and most liquids in the United States (approximately 0.95 liters).
  • US dry quart — used for some agricultural and dry goods measures; it is slightly larger than the US liquid quart.
  • Imperial quart — used historically and in some current contexts in the United Kingdom and countries that used the imperial system (approximately 1.14 liters).

In both imperial and US systems, a quart equals two pints. In American culinary practice a quart is also four cups (US cups), while cup-based relationships differ under other systems.

History and origin

The word quart comes from the Latin quartus, meaning "fourth." Traditional European measures divided a gallon into fourths, giving rise to the quart. Over centuries the sizes of gallons and related measures varied regionally. During the 18th and 19th centuries several countries moved to standardize their definitions, producing the separate modern forms (notably the US and imperial gallons) whose quarters are the quarts used today.

Uses and examples

Quarts are common in everyday life: recipes, milk and cream packaging, small fuel containers, and many retail sizes are denominated in quarts. In scientific and technical contexts the metric system is preferred, but quarts remain meaningful for consumer goods and historical records. Retail labels often mark volumes as "qt" or "qt. (US)."

Notable distinctions and facts

Key points to remember:

  • It is always one quarter of a gallon, but the gallon definition varies between systems — see the relationship to gallon.
  • A quart equals two pints, which helps when converting within the same measurement system.
  • Abbreviations such as "qt" are commonly used on packaging and recipes.

For further reading on units and conversions consult general references on measurement systems or guides comparing imperial and US customary units (measurement overview, volume concepts).