Call us today: 01438 532 300

A Comprehensive Guide to Data Centre Rack Sizes

Selecting the correct server rack size is a critical decision for businesses using data centres or hosting facilities. While the question may seem simple, the answer is far from straightforward, especially if your organisation lacks detailed data centre expertise.

Fortunately, we do! If you're assessing the next steps in upgrading your server rack, follow our guide below to ensure you make the correct decision.

Understanding server rack size

Server rack size, also known as cabinet size, refers to the overall dimensions of the racks that house servers in a data centre or hosting facility. This parameter is critical as it determines the number and types of servers a rack can accommodate, along with considerations for cables and power equipment. You want to have space big enough to meet any potential server requirements, but you don't want to end up paying for space you never use.

There are three critical dimensions determining server rack size:

  • Height

    The height of the rack is crucial as it determines the number of servers that can be stacked vertically. Standard server racks are typically around 7ft (2.1m) high, with taller options available for those needing to accommodate more servers.

  • Depth

    Server rack depth, or the distance between the front and back of the cabinet, influences the size of each server. While most servers fit within a depth of about 42 inches, some may require extra space at the rear of the rack.

  • Width

    While generally less critical than height and depth, the width of the rack can still play a role, especially in scenarios where extra space is needed for cables and power equipment.

  • Configuration

    Rack space generally comes in quarter, half, and full cabinet sizes, stretching right up to private suites for multiple racks. Make sure your data centre provider can cater for your requirements.

Unlike some industries with established standards, there is no official standard size for server racks. However, the most common size encountered is the 42U rack, designed to house 42 servers of 1 'unit' (U) each. Despite its popularity, 42U racks can vary in width and depth, with dimensions of 19 inches wide and 40 or 42 inches deep being typical. Other sizes, such as 48U racks providing additional capacity, and smaller options like 10U and 20U, are also prevalent in various use cases.

Image of the Data Centre Checklist PDF Cover

Looking for more help choosing a data centre?

If you're looking for more help choosing a data centre partner, download this free checklist to help you get the best deal.

Download the free checklist

Choosing the right rack size

With the wide array of server rack sizes available, finding a reliable data centre that can cater for your needs without going overboard is crucial in getting value.

If your requirements are modest and likely to remain static, then finding a provider who can cater for half and quarter racks is ideal. Make sure there's plenty of room for your equipment and cabling.

If quick expansion is anticipated, choosing a full rack will allow for future growth with minimal disruption and re-configuration to your operations.

For larger organisations with multiple racks' of equipment, don't be put off moving data centres if you're not getting a good deal. Assess your specific priorities, considering current and future server needs, energy efficiency requirements, and cooling methods. If these requirements aren't being met in a cost-effective way, or if your current facility is out of expansion room, then shop around. There's always support. For example, ServerChoice's FlexMove® service will move your racks free of charge.

By carefully evaluating these factors, businesses can select the optimal data centre to support their unique workloads and infrastructure. Remember, there's no one-size-fits-all solution: it's about finding the perfect fit for your business's evolving needs.

If all of this sounds confusing, get in touch so we can help guide you through the process.

Some of our customers

  • Deutsche Telekom UK - ServerChoice Customer
  • Euroffice - ServerChoice Customer
  • VisitBritain - ServerChoice Customer
  • Konica Minolta - ServerChoice Customer
  • Formula One Autocentres - ServerChoice Customer
  • Seajacks - ServerChoice Customer

SCDC provide excellent levels of skill within their team. They took me as a customer tremendously seriously and continue to do so after the PO and cheques have been signed.

The facility is better than Tier 4 in many regards, and the high level of security exceeded our expectations. It’s a great service and I know we can rely on it.

Get a quote today

For a same-day, hassle-free quote, please fill in the information below: