Kelvin Converter

The Kelvin scale is the base unit of thermodynamic temperature in the International System of Units (SI). Unlike Celsius and Fahrenheit, which are relative scales, Kelvin is an absolute scale, meaning 0 K is absolute zero—the point where all thermal motion ceases. This makes it the standard for scientific and engineering work. Our Kelvin Converter simplifies the process of converting between Kelvin, Celsius, and Fahrenheit.

Understanding the Kelvin Scale

• Absolute Zero: 0 K is the coldest possible temperature.
• No Degrees: Temperatures in Kelvin are not referred to as "degrees." We simply say "Kelvin" (e.g., 273.15 K).
• Direct Proportionality: Because it's an absolute scale, a temperature of 200 K is twice as hot (in terms of thermal energy) as 100 K. This is not true for Celsius or Fahrenheit.
• Water's Triple Point: The scale is formally defined by setting the triple point of water (where it can exist as a solid, liquid, and gas simultaneously) to exactly 273.16 K.

Conversion Formulas

The conversions between Kelvin and other scales are linear and based on a simple offset.

• Kelvin to Celsius: The size of one unit is the same in both scales. The only difference is the starting point.

  Celsius = Kelvin - 273.15

• Celsius to Kelvin:

  Kelvin = Celsius + 273.15

• Kelvin to Fahrenheit: This requires a two-step conversion, first to Celsius and then to Fahrenheit.

  Fahrenheit = (Kelvin - 273.15) * 9/5 + 32

• Fahrenheit to Kelvin:

  Kelvin = (Fahrenheit - 32) * 5/9 + 273.15

Practical Example

Let's convert a comfortable room temperature of 25°C to Kelvin and Fahrenheit:

• To Kelvin: 25 + 273.15 = 298.15 K
• To Fahrenheit: (25 * 9/5) + 32 = 45 + 32 = 77°F

Our calculator performs these conversions instantly, saving you time and preventing manual errors.