You’ve probably noticed the three-digit number on egg cartons and assumed it was random. It isn’t. That number is “your best clue to freshness and safety,” and ignoring it can turn a simple meal into an unpleasant experience.The three-digit code is the Julian date, which shows the day of the year the eggs were packed. For example, “001 = January 1” and “365 = December 31.” If a carton reads “120,” the eggs were packed on April 30. As the article clearly notes, “This is NOT the expiration date—it’s the pack date.”

According to the USDA, “Raw eggs in the shell are safe for 3–5 weeks after the pack date—even if the ‘sell-by’ date has passed.” Proper storage matters just as much. Eggs should be kept “at or below 40°F (4°C),” since warmer temperatures shorten their shelf life. The text also warns that the “sell-by” or “best-by” date is mainly for store inventory, not a true safety cutoff.

Even eggs that look and smell fine can cause illness. “Salmonella doesn’t change an egg’s appearance, smell, or taste,” which means there’s no easy way to detect it. The bacteria is only destroyed by cooking eggs to “160°F/71°C.” If eggs are old, poorly stored, or undercooked, dishes like quiche may not reach a high enough internal temperature to be safe. It’s also important to remember that “Salmonella can be inside the egg before the shell forms—so washing the shell won’t help.”

To use the Julian date safely, find the number on the carton, calculate the pack date, and use the eggs within 3–5 weeks. The advice is simple and firm: “When in doubt, toss it out—especially for dishes like quiche, hollandaise, or tiramisu that use undercooked eggs.”

That small number on the carton isn’t decoration; it’s a freshness timestamp. As the article sums it up, “Freshness isn’t just about taste—it’s about safety.” Checking the Julian date takes seconds, but it can save you from a very uncomfortable meal.