Eggs do expire and after expiration they usually go bad within a few days from the expiration date.
The sell by date and expiration date is most often on the egg carton.
You should always purchase eggs before the sell by date or expiration date on the carton.
Eggs that you buy in stores should be kept refrigerated and used within 2 to 4 weeks of purchasing it.
However some eggs may still remain safe to eat after 5 weeks from the day you purchased them and placed the eggs in the refrigerator.
You can tell if eggs are bad by using an egg floating test.
To conduct a float test, fill a bowl or cup with water (it should be big enough to fully submerge your egg).
Gently place your egg inside and see if it sinks or floats.
If it floats, it's old and you may want to toss it.
When cracked open the bad egg will smell really rotten and make you gag.
Old eggs are safe to eat as long as the old eggs have not actually gone bad and spoiled.
Spoiled eggs are never safe to eat and can make you sick and cause food poisoning and even death in some cases.