Recommended Refrigerator Temperature: Fridge at 40°F (4°C) or Below, Freezer at 0°F (-18°C)
The FDA recommends keeping your refrigerator at or below 40°F (4°C) and your freezer at 0°F (-18°C). Here is how to check it with a thermometer, what the dial numbers mean, where the warm spots are, the settings for Canada, the UK and Australia, and what to do when it will not hold temperature.
Still stuck after this guide? You can ask an HVAC technician online — see pricing, expert credentials and common questions first.
The Short Answer
Keep your refrigerator at or below 40°F (4°C) and your freezer at 0°F (-18°C). That is the U.S. Food and Drug Administration's recommendation, because bacteria multiply quickly above 40°F. Many people aim for about 37°F (3°C) to leave a margin, since the door and the front of the shelves run warmer. Check with an appliance thermometer, because the dial on the fridge is not a thermometer.
What Temperature Should a Fridge Be in Your Country?
| Country | Refrigerator | Freezer | Source |
|---|---|---|---|
| United States | 40°F (4°C) or below | 0°F (-18°C) | FDA |
| Canada | 4°C (40°F) or lower | -18°C (0°F) or lower | Health Canada |
| United Kingdom | 5°C or below | -18°C is the usual target | Food Standards Agency (fridge) |
| Australia and New Zealand | 5°C or below | -18°C is the usual target | Food Standards Australia New Zealand (fridge) |
The differences are small. Setting the fridge to about 3°C (37°F) keeps you inside every country's guidance.
How Do You Check Your Fridge Temperature?
- Buy an appliance thermometer. They are inexpensive and sold at grocery and hardware stores. The display on many fridges shows the setting, not a measured reading.
- Fridge: USDA guidance is to put the thermometer in a glass of water in the middle of the fridge and read it after 5 to 8 hours.
- Freezer: place the thermometer between frozen packages and read it after 5 to 8 hours.
- Adjust in small steps. Most manufacturers say to wait about 24 hours after a change before checking again.
- Leave a thermometer in each compartment so you can check at a glance, especially after a power outage.
What Do the Numbers on the Fridge Dial Mean?
On many refrigerators with a 1 to 5 or 1 to 9 dial, the numbers are cooling levels, not degrees. On most of these, a higher number means colder. Some models work the other way, so check your manual or the label inside the fridge. A middle setting is a common starting point; then use a thermometer and adjust.
Fridges with a digital display let you set the temperature directly. Even then, confirm with a thermometer once, because a sensor reading near the controls can differ from the middle of the shelves.
Where Is the Coldest and Warmest Part of a Fridge?
| Area | Temperature | Best for |
|---|---|---|
| Door shelves | Warmest | Condiments, juice, butter. Not milk or eggs. |
| Upper shelves | Steady, moderate | Leftovers, drinks, ready-to-eat foods |
| Lower shelves (back) | Usually coldest | Milk, eggs, raw meat and fish on a plate or in a container so nothing drips |
| Crisper drawers | Humidity controlled | Vegetables (higher humidity) and fruit (lower humidity) |
| Near the cold air vent | Can freeze food | Keep delicate produce away from it |
Do not pack the fridge so tightly that air cannot circulate, and do not block the vents.
Why Is My Fridge Too Warm or Freezing Food?
| Problem | Likely cause | Fix |
|---|---|---|
| Fridge above 40°F, freezer fine | Blocked vent between freezer and fridge, failed evaporator fan, or a damper problem | Clear the vents. If you cannot hear the freezer fan, see refrigerator running but not cooling. |
| Both compartments warm | Dirty condenser coils, fridge too close to the wall, failing compressor or defrost problem | Clean the coils, give it space to breathe, then troubleshoot |
| Food freezing in the fridge | Setting too cold, or food sitting in front of the cold air outlet | Turn the setting one step warmer and move food away from the vent |
| Temperature creeps up during the day | Worn door gasket, door left ajar, or a hot room | Close the door on a sheet of paper: if it slides out easily, the gasket is leaking |
| Freezer frost building up | Door not sealing, or a defrost system fault | Check the gasket and the door alignment |
| Loud buzzing with poor cooling | Fan or compressor trouble | See fridge making a loud buzzing noise |
How Long Is Food Safe When the Power Goes Out?
According to the FDA, a refrigerator keeps food cold for about 4 hours if you keep the door closed. A full freezer holds its temperature for about 48 hours with the door closed; USDA guidance puts a half-full freezer at about 24 hours.
When the power comes back, check the thermometers. USDA advises throwing out perishable food that sat above 40°F for more than 2 hours. Frozen food that still has ice crystals or is at 40°F or below can generally be refrozen. When in doubt, throw it out.
Call an appliance technician if the fridge cannot get below 40°F after you have cleaned the coils and cleared the vents, the compressor clicks on and off without cooling, or you see oil or smell refrigerant. Want a quick second opinion first? Ask a home repair expert.
Pro Tips
Frequently Asked Questions
What temperature should my refrigerator be?
At or below 40°F (4°C), according to the FDA. Many people set it to about 37°F (3°C) to stay safely under that limit.
What temperature should my freezer be?
0°F (-18°C). Food kept at 0°F stays safe, although quality slowly declines over time.
Is 1 or 5 colder on a fridge?
On most fridges with a numbered dial, the higher number is colder because it means more cooling. Some models are the other way around, so check the manual and confirm with a thermometer.
What is the ideal fridge temperature in Celsius?
The FDA and Health Canada say 4°C or below. The UK Food Standards Agency and Food Standards Australia New Zealand say 5°C or below. Setting about 3°C meets all of them.
Why is my fridge freezing my food?
Usually the setting is too cold or the food is right in front of the cold air vent. Turn the control one step warmer, move food away from the vent, and check again after 24 hours.
How long does food last in the fridge without power?
About 4 hours if the door stays closed, according to the FDA. A full freezer lasts about 48 hours with the door closed, and USDA puts a half-full freezer at about 24 hours.
