Convert Temperature from Degree Fahrenheit to Kelvin (F to K)

degree Fahrenheit to Kelvin Conversion Formula

To convert from degree Fahrenheit (F) to Kelvin (K), use the following formula:

Example

Let's convert 5 degree Fahrenheit (F) to Kelvin (K).

Using the formula:

Therefore, 5 degree Fahrenheit (F) is equal to $258.15$ Kelvin (K).

What is a degree Fahrenheit (°F)?

A degree Fahrenheit (°F) is the unit of temperature used in the imperial system of measurement.

Who Invented the Fahrenheit Scale?

The Fahrenheit scale was created in 1724 by the German physicist Daniel Gabriel Fahrenheit. He based his scale on three fixed points:

• The zero point (0 °F) was set by the temperature of a freezing mixture of brine (ice, water, and ammonium chloride).
• The second point (32 °F) was the freezing point of water, and the third (96 °F) was his best estimate of the average human body temperature.
• Later, the scale was tweaked so that the boiling point of water is exactly 212 °F—a full 180 degrees above freezing.

Where Is the Fahrenheit Scale Used Today?

While most of the world has adopted the Celsius scale for everyday temperature measurement, the Fahrenheit scale remains the official scale in the United States, its territories (like Puerto Rico and Guam), and a few other countries, including the Bahamas, Palau, and the Cayman Islands.

In the United Kingdom, both Fahrenheit and Celsius are used to describe temperature; Fahrenheit remains more familiar to older people and is often heard in casual conversation.

How to Convert Fahrenheit to Celsius (Formula)

You can easily convert any temperature from Fahrenheit to Celsius using a simple formula. To convert a temperature from Fahrenheit (F) to Celsius (C), subtract 32 from the Fahrenheit temperature and then multiply the result by 5/9.

The Fahrenheit to Celsius formula is: C = (F − 32) × 5/9

For example, to convert a pleasant day of 77 °F to Celsius: C = (77 − 32) × 5/9 = 45 × 5/9 = 25 °C

What is a Kelvin (K)?

The kelvin (K) is a unit of measurement for temperature, similar to the Celsius and Fahrenheit scales. What sets it apart?

Most people typically refer to temperature in Fahrenheit or Celsius. Still, scientists favor Kelvin due to its status as an absolute scale. This means it starts at the lowest possible temperature in the universe, making it ideal for accurate scientific research.

It's also one of the seven base units in the International System of Units (SI).

What Is Absolute Zero?

The Kelvin scale begins at 0 K, a point known as absolute zero. This isn't just a random number—it's the theoretical temperature where all atomic motion would completely stop. It's the ultimate cold.

Unlike Celsius, where 0° is the freezing point of water, 0 K is based on a fundamental truth of the universe. This non-arbitrary starting point is why scientists in fields like physics and astronomy rely on it.

Why Is the Kelvin Scale Important?

While you won't use Kelvin to check the daily weather, it's essential in many scientific and technological fields.

• Astronomers use it to measure the frigid temperatures of deep space and the scorching heat of stars.
• Physicists need it for experiments in quantum mechanics and superconductivity.
• Engineers use it when working with materials at extreme temperatures, from rocket engines to medical MRI machines.

How to Convert Between Kelvin and Celsius

The good news is that converting between Kelvin and Celsius is very easy. The size of one unit is identical in both scales, meaning a change of 1 K is the same as a change of 1 °C.

Here are the conversion formulas you need:

• To convert Celsius to Kelvin: Add 273.15 to your Celsius temperature.
  • Formula: K = °C + 273.15
• To convert Kelvin to Celsius: Subtract 273.15 from your Kelvin temperature.
  • Formula: °C = K - 273.15

Examples:

• Water freezes at 0 °C, which is 273.15 K.
• A pleasant room temperature is approximately 20 °C, which corresponds to 293.15 K.
• Water boils at 100 °C, which is 373.15 K.

Who Invented the Kelvin Scale?

The scale is named after its inventor, the brilliant Scottish engineer and physicist William Thomson, 1st Baron Kelvin (1824–1907). In 1848, he introduced an "absolute" thermometric scale beginning at what he called "infinite cold" — the temperature now known as absolute zero. His work established the foundational principles of a measurement system central to modern science.

What is the imperial system?

What is the metric system?

degree Fahrenheit to Kelvin Conversion Table

Here are some quick reference conversions from degree Fahrenheit (F) to Kelvin (K):