Food & cooking · Emergency preparedness
Power outage food safety calculator.
Enter how long the power has been out and how full the freezer is, and see how much safe time is left for the fridge and freezer.
Inputs
Fridge and freezer
Enter the numbers above.
How long is food safe in a power outage?
Health Canada says an unopened refrigerator keeps food cold for about 4 hours, a full freezer keeps food frozen for about 48 hours, and a half-full freezer for about 24 hours, as long as you do not open the doors. Ready.gov gives the same 4 hours and 48 hours. Subtract the hours without power from each limit to see the time left.
Worked example. The power has been out 6 hours and the freezer is half-full. The fridge limit is 4 hours, so it is 2.0 hours past the limit. The half-full freezer limit is 24 hours, so 24 - 6 = 18.0 hours are left.
These are time estimates, not a test. Use a thermometer: Ready.gov says to throw out food if the temperature is 40 °F (4 °C) or higher, and Health Canada says to throw away all food that has been at room temperature for 2 or more hours and anything with an unusual colour or odour. After the power returns, food that still contains ice crystals or feels refrigerator-cold can be re-frozen. When in doubt, throw it out.
Frequently asked questions
How long does food last in a fridge without power?
About 4 hours if the door stays closed, according to Health Canada and Ready.gov. Health Canada says not to open the refrigerator or freezer door unless necessary, because opening it lets the cold out.
How long does a freezer stay frozen without power?
Health Canada says about 48 hours when full and about 24 hours when half-full, if unopened. Public Safety Canada’s power-outage page gives a range of 24 to 48 hours for a full freezer, so use the half-full setting if you want the cautious figure.
Can I put food outside in winter?
No. Health Canada says not to place frozen food outside, even in winter: animals could get it, and the sun can thaw it even when the air is very cold.
Can I refreeze food after an outage?
Health Canada says food that still contains ice crystals or feels refrigerator-cold can be re-frozen, and it is safe to eat if cooked to safe internal temperatures. Throw out anything at room temperature for 2 or more hours.
What temperature means I should throw food out?
Ready.gov says to throw out food if the temperature is 40 °F (4 °C) or higher. Monitor with a thermometer.
Sources
Checked
- Health Canada, "Food and drinking water safety in an emergency" (page dated 8 May 2026), opened 8 October 2026. fridge about 4 hours, freezer 48 and 24 hours, 2 hours at room temperature, re-freezing, no frozen food outside
- Public Safety Canada, Get Prepared, "How to prepare before a power outage" (page dated 12 March 2026), opened 8 October 2026. full freezer 24 to 48 hours, keep fridge and freezer closed
- Ready.gov, "Power Outages", opened 8 October 2026. fridge about four hours, full freezer about 48 hours, throw out food at 40 F or higher
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Food safety note
Food safety times are rules of thumb that assume closed doors; real temperatures depend on the appliance, room temperature and how full it is. Medications that need refrigeration should be checked with your pharmacist.