1 Keep the refrigerator temperature at or below 40° F (4° C). 2  The freezer temperature should be 0° F (-18° C). 3  Check temperatures periodically. 4  Appliance thermometers are the best way of knowing these temperatures and are generally inexpensive. Also, when putting food away, don't crowd the refrigerator or freezer so tightly that air can't circulate. 2  Keep your appliances at the proper temperatures. 3  Keep the refrigerator temperature at or below 40° F (4° C). 4  The freezer temperature should be 0° F (-18° C).