Calculator
Left-out checker
Enter the food and how long it sat out. We apply USDA's 2-hour rule (1 hour above 90°F) to that specific food.
Keep or discard appears here.
Why 2 hours?
Bacteria such as Salmonella, Staphylococcus aureus and Bacillus cereus double quickly between 40°F and 140°F (4–60°C) — FSIS calls this the danger zone. Two hours is the limit before numbers or toxins can reach unsafe levels. In hot weather, the limit is one hour.
See every food on one page: food left out overnight, A–Z.
FAQ
What is the 2-hour rule?
Perishable food should not sit between 40°F and 140°F for more than 2 hours, or 1 hour when it is above 90°F (32°C).
Does it matter if the food was cooked?
Cooked food is still perishable. Cooked rice, meat, pasta and sauces all follow the 2-hour rule.
Is it safe if I reheat it?
No. Some bacteria produce toxins that heat does not destroy. Food left out too long should be thrown away.
What foods are safe to leave out?
Shelf-stable foods: bread, whole fruit, most condiments before opening, dry goods. Check each food's page.
More tools: Leftover calculator · Freezer time calculator · Thaw time calculator · Best-by date decoder
Numbers on this page come from USDA FoodKeeper and FSIS guidance. Last verified November 2026. How we verify our data · Report a wrong number