Convert degrees Fahrenheit to kelvin

Explanation

To convert degrees Fahrenheit to kelvin add 459.67 then multiply by 5 and divide by 9.

Formula

(°F + 459.67) × 5 / 9=K

degrees Fahrenheit°F

dimension	temperature
symbol	°F
search alias	f

The degree Fahrenheit (°F) is a unit of temperature.

Definition

The Fahrenheit scale uses the freezing and boiling point of water as fixed reference points. The values associated to these two points are 32 °F and 212 °F respectively.

History

In its original proposal in 1724, Fahrenheit used the temperature of a solution of brine to set the 0 of his scale and the average temperature of the human body was set at 96 °F. 32 °F was marked as the temperature of freezing water.

Following the work of Anders Celsius, the Fahrenheit scale was redefined in 1776 to the present definition. This redefinition changed the temperature of the original solution of brine to approximately 4 °F and the average human body temperature to 98.6 °F.

Related Conversions

kelvinK

dimension	temperature
system	International system of units (SI)
symbol	K

The kelvin (K) is the unit of temperature of the International System of Units.

Definition

It is defined by taking the fixed numerical value of the Boltzmann constant k to be 1.380 649 × 10^–23 when expressed in the unit J K^–1, which is equal to kg m² s^–2 K^–1, where the kilogram, metre and second are defined in terms of h, c and ∆ν_Cs.

From the BIPM: Thermometry: SI base unit

History

The kelvin was first defined in 1954 using the triple point of water to which the temperature 273.16 K was assigned. This definition proved to be impractical and was replaced on 20 May 2019 by the present definition.