What temperature should your refrigerator and freezer be?

The refrigerator should hold at or below 40 degrees Fahrenheit and the freezer at 0 degrees. The 40-degree threshold is the top of the danger zone in which bacteria multiply rapidly, and the practical target is closer to 37 to 38 to leave margin during door openings and warm-food additions. Zero in the freezer stops bacterial growth entirely and preserves quality, though food remains safe indefinitely at that temperature even as texture and flavor degrade over months.

Verify with a standalone appliance thermometer rather than the built-in display, which measures at one location and is frequently inaccurate by several degrees. Place it in the middle of a shelf and check after the door has been closed for several hours. Temperature varies considerably within the compartment: the door is the warmest area because it is exposed on every opening, which makes it the wrong place for milk, eggs, and anything else where consistent cold matters, despite manufacturers having built egg trays there for decades. The back of the lower shelves is coldest and is where raw meat belongs, both for temperature and because it prevents drips onto food below.

Two operational points. Airflow matters, so an overpacked refrigerator develops warm pockets while a nearly empty one loses temperature faster on opening, and blocking the vents inside is a common cause of uneven cooling. A freezer, conversely, runs most efficiently when full. And during a power outage, a closed refrigerator holds safe temperature for about four hours and a full freezer for roughly 48 hours, half that if half full, which is why the instruction is to keep the doors shut rather than checking. When power returns, judge by temperature rather than appearance or smell: food above 40 degrees for more than two hours should be discarded, and frozen food that still contains ice crystals can generally be refrozen.