Food Safety: How long is food allowed to be out?

October 9, 2025 •

3 min read

According to the Centers for Disease Control and Prevention (CDC), bacteria can multiply rapidly if left in the 'temperature danger zone' between 40°F and 140°F. Understanding how long is food allowed to be out is crucial to prevent food poisoning and maintain a safe nutrition diet.

Quick Summary

This guide explains the critical time limits for leaving perishable food unrefrigerated, focusing on the two-hour rule and the temperature danger zone. Key food safety practices, specific food handling guidelines, and tips for safe storage are covered to minimize the risk of foodborne illnesses.

Key Points

The Two-Hour Rule: Never leave perishable food out at room temperature for more than two hours, or one hour if the temperature is above 90°F.
The Danger Zone: Bacteria multiply fastest between 40°F and 140°F, so keep hot foods hot and cold foods cold to avoid this temperature range.
Cooling Leftovers: Divide large quantities of food into shallow containers for quicker cooling before refrigerating within two hours.
Discard When in Doubt: Never rely solely on a food's appearance or smell to determine its safety; if it has been left out too long, it's safer to discard it.
Avoid Cross-Contamination: Use separate cutting boards and utensils for raw and cooked foods to prevent transferring harmful bacteria.
Reheating Thoroughly: Always reheat leftovers to an internal temperature of 165°F, but remember this doesn't reverse spoilage if food was left out too long.

Understanding the 'Two-Hour Rule'

The 'two-hour rule' is a fundamental food safety guideline stating that perishable foods should not be left at room temperature for more than two hours. The timer begins when food is no longer being heated or chilled. This rule is vital because of the 'temperature danger zone,' where bacteria can proliferate rapidly.

The Temperature Danger Zone: A Breeding Ground for Bacteria

Bacteria, including harmful types like Salmonella and E. coli, grow fastest between 40°F and 140°F (5°C and 60°C). In this 'danger zone,' bacteria can double every 20 minutes. Keeping food out of this zone through proper chilling or heating is one of the four key steps to food safety: Clean, Separate, Cook, and Chill.

Adjusting the Rule for High Temperatures

When temperatures reach 90°F (32°C) or higher, such as during warm weather, the safe time for leaving perishable food out is reduced to just one hour.

Guidelines for Specific Food Types

Certain foods pose higher risks if left out. Cooked rice, for example, can contain Bacillus cereus bacteria if not handled properly. Mayonnaise-based salads are also risky, as the less acidic ingredients support bacterial growth in the danger zone.

Leftovers must be cooled quickly and refrigerated within two hours. Dividing large hot items into shallow containers helps speed cooling. Most leftovers are safe in the fridge for 3 to 4 days, while items like cooked rice and pasta are best consumed within 2 days.

Comparing Safe Handling Practices


Handling Situation	Temperature Guideline	Time Limit	Special Considerations
Room Temperature (below 90°F)	40°F to 140°F (Danger Zone)	2 hours	Covers most home situations and cooler weather. After 2 hours, discard.
High Heat (above 90°F)	40°F to 140°F (Danger Zone)	1 hour	Critical for summer picnics, barbecues, or leaving food in a hot car. Discard after 1 hour.
Refrigeration	Below 40°F (Below 5°C)	3 to 4 days (for most items)	Cool large items in shallow containers. Consume leftovers within the safe timeframe. Discard if unsure.
Hot Holding	At or above 140°F (At or above 60°C)	Indefinite (while maintaining temp.)	Use warming trays, slow cookers, or chafing dishes. Once removed from heat, the two-hour rule applies.
Freezing	At or below 0°F (-18°C)	Indefinite (safety)	Freezing halts bacterial growth but doesn't destroy all bacteria. Quality may degrade over time. Thaw safely in the fridge, not on the counter.

Practical Food Safety Tips

For a safer kitchen and diet, remember these key practices:

Cool Food Rapidly: Divide large portions into shallow containers to cool quickly before refrigerating.
Never Rely on Appearance or Smell: Food left out too long may not look or smell bad but can still be unsafe. When in doubt, throw it out.
Handle Raw and Cooked Foods Separately: Prevent cross-contamination by using different utensils and cutting boards for raw meat and produce.
Reheat Thoroughly: Reheat leftovers to 165°F. However, reheating doesn't guarantee safety if food was left out too long.
Use Proper Storage Containers: Store leftovers in airtight containers, labeled and dated to track storage time.

Conclusion

Following the two-hour rule is essential for preventing foodborne illness. By understanding the 'temperature danger zone' and practicing safe food handling—especially with leftovers and during warmer temperatures—you can significantly reduce health risks. Prompt cooling, refrigeration, and discarding questionable food ensure your meals are safe. Remember, when in doubt, throw it out.

For more detailed food safety guidelines, you can consult official resources like the USDA's Food Safety and Inspection Service.

Note: This content is for informational purposes. For specific medical advice, consult a healthcare professional.

Frequently Asked Questions

The 'temperature danger zone' is the range between 40°F (5°C) and 140°F (60°C) where harmful bacteria can multiply rapidly. Perishable food should be kept out of this range.

Most leftovers can be safely kept in the refrigerator for 3 to 4 days, provided they were refrigerated promptly within two hours of cooking. Items like cooked rice and pasta may only last 2 days.

No, it is not safe. Reheating food does not kill all of the toxins produced by some bacteria that may have grown while the food was in the danger zone.

During a power outage, keep refrigerator and freezer doors closed as much as possible. Perishable food that has been above 40°F for more than two hours should be discarded.

No, cooked rice should not be left at room temperature for hours. It must be cooled rapidly and refrigerated within two hours to prevent the growth of Bacillus cereus bacteria.

You cannot reliably tell if food is safe by its appearance or smell alone. The bacteria that cause foodborne illness do not always produce a noticeable odor or change in texture. If food was left in the danger zone too long, you should discard it.

Like other perishable items, mayonnaise-based salads and dishes should not be left out for more than two hours. The time reduces to one hour if the temperature is 90°F or above.