# Rack unit

A Rack Unit (RU) is a unit of measure that describes the height of equipment designed to be mounted in a 19-inch rack. One RU is equal to 1.75 inches (4.445 cm). What is a racking unit? A racking unit is a physical device that houses and supports servers, storage, and networking equipment in a data center. Racking units come in various sizes and can be configured to support different types of equipment.

#### What does 1U 2U 3U 4U mean?

1U, 2U, 3U, 4U are all measurements of height for server racks and cabinets. 1U is 1 unit of height, which is equal to 1.75 inches (4.445 cm). 2U is 2 units of height, which is equal to 3.5 inches (8.89 cm). 3U is 3 units of height, which is equal to 5.25 inches (13.335 cm). 4U is 4 units of height, which is equal to 7 inches (17.78 cm). How much is 1U rack space? 1U rack space is 1.75 inches (4.4 cm) high. How big is a 42U rack? A 42U rack is approximately 42 inches wide, 42 inches deep, and 84 inches tall. What does 1U 2U mean? 1U and 2U are terms used to describe the height of computer servers and other equipment designed to be installed in a 19-inch rack. 1U is 1.75 inches (4.4 cm) and 2U is 3.5 inches (8.9 cm).