OEE, or Overall Equipment Effectiveness is a valuable set of metrics that explain how well a machine, process, or a plant is operating. OEE is an index that is calculated by measuring Key Performance Indicators (KPI). These indicators include metrics such as Availability, Performance, and Quality. Availability measures how often a machine is online and producing. Performance measures the rate or speed of production. Quality is a measure of how many nonconforming units are produced during production.