Server Racks and Their Sizes

Related Article: Buy Server Rack in Singapore: What You Need to Know

Server Rack SizesAs we know, server racks come in various types and dimensions, depending on the specific needs and the sizing of the equipment that will be mounted on it. In a particular way, the height of the rack needs to be considered, since it indicates the amount of spaces that can be occupied by the equipment.

Server racks have their own measuring unit, which is associated with the height of the device that will be installed. While the width can only have two sizes (19 or 23 inches, the first one being the standard and most common), the height increases by a rate of 1.75 inches, and this quantity is called rack unit or just “U”. That said, it is possible to understand the notation used for server rack sizing: 1U, 2U, 3U and so on.

For example, a 9U rack has a width of 19 inches (for a standard rack) and a height of 15.75 inches (1.75 multiplied by 9). The size of the rack will depend on several factors, starting with the size and type of business activity of the company, which will determine the real needs regarding the number of devices for networking, communications, or any other applications.

Evidently, the needs of a small retail shop will be different from those of a telecommunications company or a small office.

Categorization of Server Racks

Server racks can be classified according to many features but the most usual is to categorize them by size.  We have grouped them in three general categories, considering the area of application.

1U to 12U Server Racks

These rack sizes have a common usage on IT applications. They can vary depending on each specific case, where space, traffic and other conditions must be taken into account.

Smaller racks, usually ranging from 1U up to 6U are used for low height installations that count with some kind of anchoring for wall mounting or for that equipment that can be placed on the ground. These are often found in telecommunication applications as well as monitoring equipment.

It is important to consider their weight capacity due to the fact that some devices (such as UPS’s, among others) might need a strong structure in order to be securely held.

18U, 22U and 32U server racks

These are the most common among the medium size racks. Telecommunication devices, servers and network equipment can be stored in these structures, allowing visibility, good ventilation and many possibilities of arrangement.

This is a good option for small equipment, which provides security as well as a higher capacity in terms of weight.
Among the advantages of this group of server racks, we can mention the following:

  • Easy and fast assembly
  • Great mobility (most of them are provided with wheels so that it is possible to move them from one place to other)
  • Versatility when mounting and arranging the equipment thanks to the adjustable mounting option, with removable doors
  • Security and safe functioning, with a structure that allows ventilation for the system

“Higher-U” Server racks: 42U, 45U and 48U

Most racks are 42U, (about two meters high) which are used for professional audio and video equipment, and of course, for housing the biggest servers and IT networks. This size allows an efficient arrangement of all the components as well as an important saving of space, a very significant feature when it comes to such an amount of devices.

Industrial energy and automation hardware are also two of the main uses of large-size racks; the range of 45U-48U is the most common in this type of companies.
These racks are floor-standing structures and sometimes they can be customized in order to reach up to 58U for special cases in which there are a huge number of devices, for example, high-density data centers.

In addition, this category of server racks allows the possibility for a future expansion of the equipment, a great benefit for fast-growing businesses. They are also suitable if extra space is needed for cabling and other connections.

Compatibility with additional accessories is also an important feature. These racks are designed in a way that facilitates the maintenance of the equipment, an efficient airflow and allow a simple and fast installation.

Summary of the Sizes of Popular Server Racks

We have summarized the sizes of the most popular server racks in Singapore in the table below, so you can easily refer to it to find the most suitable server rack for your office or home:

Popular Server Racks & Sizes
How Many U?Height (cm)Width (cm)Depth (cm)
6U Server Rack (A)36.86045
6U Server Rack (B)36.86060
9U Server Rack (A)50.16045
9U Server Rack (B)50.16060
12U Server Rack63.56060
18U Server Rack98.86060
22U Server Rack116.66060
32U Server Rack1616060
42U Server Rack (A)205.56060
42U Server Rack (B)205.56080
42U Server Rack (B)205.560100