# Degree of temperature

In the context of temperature, a degree is defined as a set change in temperature when measured against a given scale, such as the Celsius or Fahrenheit scales.

The term "degree" is used in a number of different mathematical contexts. Some of these include the unit of angle measurement, named the degree, which uses a symbol, also called a degree (°). It can also be used to refer to the degree of a polynomial, which is determined by the highest order exponent of the polynomial. This page will focus on the degree as a unit of measurement of temperature.

## Temperature scales and degrees

The most commonly used temperature scale around the world is the Celsius scale. In the past, the Celsius scale was defined around the freezing (0 °C) and boiling (100 °C) points of water. Today, the definition is based on the Boltzmann constant and kelvin, but the size of a degree Celsius has not changed. One degree on the Celsius scale is defined as one hundredth of the temperature change between the freezing point and boiling point of water.

The Fahrenheit scale is a temperature scale that is used mostly in the United States and its territories. Most other countries use the Celsius scale instead. The Fahrenheit scale is defined based on the freezing and boiling points of water, but the magnitude of each degree is different from that in the Celsius scale. One degree Fahrenheit is of the interval between the freezing and boiling point of water. The freezing point of water is at 32 °F on the Fahrenheit scale, and the boiling point is at 212 °F.

Unlike either the Celsius or Fahrenheit scales, the Kelvin scale does not use degrees. Each temperature increment in the Kelvin scale is simply referred to as 1 kelvin (K), rather than "1 °K," which is an incorrect use of the kelvin. The kelvin is the base unit of temperature in the International System of Units (SI). It is used primarily in scientific contexts, but since the temperature increments on the Kelvin scale are equal to those of the Celsius scale (1 degree Celsius is the same size as 1 kelvin), they are often used together.