The temperature danger zone
Every answer on this page is the words of the U.S. Department of Agriculture’s Food Safety and Inspection Service or the Food and Drug Administration, quoted whole lines at a time from the page named under each quote, on the day given there.
What is the temperature danger zone?
Leaving food out too long at room temperature can cause bacteria (such as Staphylococcus aureus, Salmonella Enteritidis, Escherichia coli O157:H7, and Campylobacter) to grow to dangerous levels that can cause illness. Bacteria grow most rapidly in the range of temperatures between 40 °F and 140 °F, doubling in number in as little as 20 minutes. This range of temperatures is often called the "Danger Zone."
USDA FSIS, Danger Zone (40°F - 140°F), retrieved 14 November 2026. Quoted word for word.
How long can food be left out of the refrigerator?
Never leave food out of refrigeration over 2 hours. If the temperature is above 90 °F, food should not be left out more than 1 hour.
Keep hot food hot—at or above 140 °F. Place cooked food in chafing dishes, preheated steam tables, warming trays, and/or slow cookers.
Keep cold food cold—at or below 40 °F. Place food in containers on ice.
USDA FSIS, Danger Zone (40°F - 140°F), retrieved 14 November 2026. Quoted word for word.
How long can eggs be unrefrigerated?
Refrigerate or freeze perishables right away. Foods that require refrigeration should be put in the refrigerator as soon as you get them home. Stick to the "two-hour rule" for leaving items needing refrigeration out at room temperature. Never allow meat, poultry, seafood, eggs, or produce or other foods that require refrigeration to sit at room temperature for more than two hours—one hour if the air temperature is above 90° F. This also applies to items such as leftovers, "doggie bags," and take-out foods. Also, when putting food away, don't crowd the refrigerator or freezer so tightly that air can't circulate.
FDA, Are You Storing Food Safely?, retrieved 4 November 2026. Quoted word for word.
How fast must leftovers go into the refrigerator?
One of the most common causes of foodborne illness is improper cooling of cooked foods. Bacteria can be reintroduced to food after it is safely cooked. For this reason leftovers must be put in shallow containers for quick cooling and refrigerated at 40 °F or below within two hours.
USDA FSIS, Danger Zone (40°F - 140°F), retrieved 14 November 2026. Quoted word for word.
Bacteria grow rapidly between the temperatures of 40° F and 140° F. After food is safely cooked, hot food must be kept hot at 140° F or warmer to prevent bacterial growth. Within 2 hours of cooking food or after it is removed from an appliance keeping it warm, leftovers must be refrigerated. Throw away all perishable foods that have been left in room temperature for more than 2 hours (1 hour if the temperature is over 90° F, such as at an outdoor picnic during summer).
USDA FSIS, Leftovers and Food Safety, retrieved 4 November 2026. Quoted word for word.
What about thawing on the counter?
Even though the center of the package may still be frozen as it thaws on the counter, the outer layer of the food could be in the "Danger Zone," between 40 and 140 °F — temperatures where bacteria multiply rapidly.
USDA FSIS, The Big Thaw — Safe Defrosting Methods, retrieved 4 November 2026. Quoted word for word.
How long these foods keep
Storage times from USDA FoodKeeper, each on its own page.
More from FDA and USDA FSIS
KeepsUntil is an independent reference built on public USDA data. It is not affiliated with, endorsed by, or connected to the U.S. Department of Agriculture or the Food and Drug Administration. Storage times are reproduced from USDA FoodKeeper as published; when in doubt, follow the FDA and USDA FSIS guidance linked on every food page.