Is that leftover chicken safe to eat?

Here are the standard food safety guidelines:

Situation Safe Time at Room Temperature*
Cooked Meat (Including Chicken) Up to 2 hours before refrigerating.
If ambient temperature is high (> ~90°F / 32°C) Up to 1 hour outside.
*“Room temperature” here refers to what many kitchens or indoor spaces feel like – moderate, not super hot.

Once the safe time is exceeded, meat should be thrown away – even if it smells or looks good. Appearance and odor are not reliable indicators of bacterial contamination.

Refrigeration and Storage Rules
To reduce risk and preserve leftovers:

Refrigerate immediately after cooking (or serving), preferably within 2 hours. On very hot days, do it sooner.
Use shallow, airtight containers to help food cool faster and avoid exposure to contaminants.
Store cooked chicken/poultry in the refrigerator for no more than 3-4 days. After that, bacteria can grow even in the cold.
If you don’t eat it within that time, freeze it. Freezing stops bacteria from growing.
What about reheating?
Reheating kills some bacteria, but not necessarily all of the toxins that may have formed when the food sat out too long. Once toxins have entered the food, they can cause illness, even if the bacteria themselves are killed.
When reheating, heat the meat thoroughly—make sure it’s steaming hot all the way through.
When in doubt: throw it out