Original: The coldest theoretically possible temperature is absolute zero, also called absolute temperature, which is 0 K on the Kelvin scale, a thermodynamic temperature scale, and â '273.15 Â C on the Celsius scale.
Simplified: The coldest possible temperature is â '273.15 Â C, which can be expressed as about -459.67 Â F on the Fahrenheit scale. This is called absolute zero.