You can't always go by the date on the carton of eggs, because legally the sell-by date has to be within 45 days of the pack date.  When handled and refrigerated properly, eggs can last much longer. To determine if an egg is fresh, submerge it into water. Very fresh eggs will sink to the bottom and lay on its side, while older eggs will stand up. Eggs that stand up are still safe to eat, but it is best to toss them out if they float.