What is 1U? – Explained, Plain and Simple

Written on January 10, 2017 By Support Team

Often times when people are new to the rackmount server world, there is a lot of confusion with the industry standard height measurements.

The term 1U specifies that the chassis of the server is of 1 Rack Unit Height measurement. This breaks down even easier with some simple math.

Think back to algebra and look at the U as a variable meaning 1.75 inches. In this case, 1U would just mean 1 times 1.75 inches. Thus making the server 1.75 inches tall!

Using algebra like this applies to the other measurements as well:


Racks are also seperated into Rackmount U measurments. Leaving everything in U form makes life easier for everyone involved with using the server. Instead of having to remember heights in inches and grabbing a calculator when trying to fill a rack, a person knows that if their rack is 20U high they can put 20 1U servers in the rack.

Just remember, the U is only a variable and represents an easily calculatable height for any server you’re interested in.

Our Top Custom Built Servers

Related Tags: