What is repeatability and how can it be fully established? Repeatability is the amount of closeness of a series of measurements assessing the same item or area. The closer the measurements are, the more repeatable. In essence, for repeatability you want the same measurement to repeat. While not always evident in larger production lines or projects, repeatability is incredibly important to establish, before mass production can occur. In order to establish the repeatability of your measurements, you will need to set a series of factors as stable and collect numerous data points. This is known as a repeatability test. The conditions in which repeatability is tested are crucial and include: the same item or area being measured, the same device or tool used to measure, the same operator completing the measurement, and the same environmental conditions throughout each measurement. When all of these factors are held stable and a series of measurements come out as nearly identical, the measurement can be said to be repeatable.