Popcorn's shelf life varies depending on  its state—whether it's unpopped kernels,  

air-popped, or commercially packaged.

Stored in a cool, dry place, unpopped popcorn  kernels can last indefinitely. However,  

for optimal taste and popping efficiency,  it's best to use them within 1 to 2 years.

Once popped, air-popped popcorn can  last about 1 to 2 weeks if kept in  

an airtight container at room  temperature. Its freshness and  

crispiness will diminish over time,  so it's best enjoyed within a week.

As to the commercially packaged  popcorn, the shelf life can vary  

widely depending on the type of packaging  and whether it contains preservatives.

Generally, unopened, it can last 2 to 3  months past the printed date. Once opened,  

keeping it sealed and dry can extend  its freshness for a couple of weeks.

Moisture is the enemy of popcorn, leading to  sogginess and potential mold growth. For all  

types, storing in a cool, dry place, away  from sunlight and in an airtight container,  

helps maintain its quality  and extends its shelf life.