Egg cartons can seem confusing, especially when they display several dates, codes, and numbers. One of the most useful markings is the three-digit pack date, which tells you the day of the year the eggs were processed and packaged. The numbers range from 001 to 365, with 001 representing January 1. For example, 032 means February 1, while 198 means July 17 in a non-leap year. A code beginning with “P” identifies the processing or grading facility, while “Sell By” and “Best By” dates serve different purposes.

Knowing the pack date can help you choose older cartons first, but it cannot tell you whether an egg is safe to eat. Proper refrigeration is much more important. Eggs should be kept at 40°F or below, preferably on an interior refrigerator shelf in their original carton. When stored correctly, raw shell eggs generally last about three to five weeks. But there is another important warning many people overlook: even an egg that looks and smells perfectly normal can still contain harmful bacteria.