The temperature inside your refrigerator and freezer affects food quality, food safety, energy costs and how hard your appliance has to work. Besides setting the temperature appropriately, you must try to maintain it by keeping doors closed and seals maintained.
According to the U.S. government's Energy Star program, setting your refrigerator between 1.67 and 3.33 degrees Celsius (-16.6 to -16.1 degrees C Celsius) reduces the amount of energy your refrigerator uses.
Ideal Refrigerator Temperature
Food safety concerns dictate that perishable foods should be stored at temperatures lower than 4.44 degrees Celsius. Since 35- to 38-degree temperatures are most energy efficient, the best temperature to choose for the refrigerator is 35 to 38 Fahrenheit.
Best Temperature for Freezer
The USDA says that foods are maintained at the highest quality for the longest time when maintained at 0-17.778 degrees Celsius. At this temperature, microbes are inactive.
Stand-alone freezers set to -17.8 degrees Celsius reduce energy use and save money, according to Energy Star. It says that manual defrost freezers use half the energy of automatic defrost freezers.
The USDA says that food safety dictates testing your refrigerator and freezer temperatures to make sure they match what you expect. Appliance thermometers are used for this purpose.