Data centers come in all sizes with varying power demands. Some small facilities draw just a few kilowatts (kW) while hyperscalers are in the megawatt (MW) range. Requirements for availability (uptime) can also differ greatly. The Uptime Institute classifies data centers according to the following tier ratings.
In practice, this establishes the acceptable period of downtime ranges from 144 minutes per month for Tier 1 facilities to just two minutes per month for Tier IV.