Temperature conversion formulas are mathematical equations used to convert temperature measurements from one unit to another. The most commonly used temperature scales are Kelvin, Celsius, and Fahrenheit. In the Kelvin scale, water freezes at 273.15K and boils at 373.15K. In Fahrenheit, water freezes at 32°F and boils at 212°F, while in Celsius, water freezes at 0°C and boils at 100°C.