Free tool
Left-out food checker
Tell us the food and how long it stayed at room temperature. We check it against USDA's 2-hour rule, which shrinks to 1 hour above 90°F.
Your keep-or-toss answer will show here.
Where the 2-hour limit comes from
Between 40°F and 140°F (4–60°C), a range FSIS calls the danger zone, bacteria like Salmonella, Staphylococcus aureus and Bacillus cereus multiply fast. Once two hours have passed, their numbers, or the toxins they make, can reach unsafe levels. When it is hot out, that window shrinks to one hour.
Want the full list? See every food left out overnight, A–Z.
Questions & answers
What exactly is the 2-hour rule?
Perishable food should spend no more than 2 hours between 40°F and 140°F, and no more than 1 hour once the temperature is above 90°F (32°C).
Does cooking the food change anything?
No. Cooked food is still perishable, so cooked rice, meat, pasta and sauces all fall under the 2-hour rule.
Can reheating make it safe again?
No. Certain bacteria make toxins that survive heating. If food sat out too long, throw it away.
Which foods can safely sit out?
Shelf-stable items such as bread, whole fruit, dry goods and most unopened condiments. Each food's page has the details.
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Figures here are drawn from USDA FoodKeeper plus FSIS guidance. Data re-checked November 2026. How we check our numbers · Spotted an error? Tell us