Height is a measurement of the distance from the bottom to the top of something which is upright. The measurement must be taken vertically, otherwise it is termed the length (or sometimes, the width). Like length and width, it is measured in units of length.

In geodesy, height is the metric distance of a point (usually on the terrain surface, such as a mountain top) vertically above a reference surface such as mean sea level. A more precise definition of a reference surface would be the geoid, the equipotential surface of the geopotential that coincides in the mean with mean sea level. Such heights are called orthometric heights .

Human height is one of the areas of study within anthropometry. As pointed out in an article [1] in The New Yorker, the average height of human populations appears to be a convenient metric for all the factors that make up a group's well-being. While height variations within a population are largely genetic, height variations among populations are mostly environmental. The United Nations uses height (among other statistics) to monitor nutritional standards in developing nations. In human populations, average height can distill down complex data about the group's birth, upbringing, social class, diet, and healthcare system.

See also

• International System of Units
• U.S. customary units
• Imperial units
• Chinese units (市制 or Shìzhì)