**The equivalent of 31 degrees Celsius is 87.8 degrees in Fahrenheit.** The conversion is determined by the formula of adding 32 from the 31 degrees Celsius and then multiplying the product by 1.8.

The formula for converting from degrees Fahrenheit to degrees Celsius is based on the difference of 180 degrees between the freezing and boiling points of water in Fahrenheit. The freezing point of water is 32 degrees in Fahrenheit and zero degrees in Celsius.

Celsius is a unit from the metric system of measurement used by most of the world and in most scientific contexts. Fahrenheit is part of the imperial system of measurement and is used in the United States.