How to Tell if an Egg is Rotten

If you want to be able to tell if an egg is rotten you need to read below.

There is a small air pocket in the large end of the egg. When the egg is fresh, the pocket is only about 1/8th of an inch deep and as large around as a dime. As the egg ages, however, it loses both moisture and carbon dioxide shrinking so that the size of the air space increases. And the size of the air space determines the buoyancy of the egg. So if you submerge a very fresh egg in water, it will lie on the bottom. An egg that is a week or so old will lie on the bottom but bob slightly. An egg that is three weeks or so old will balance on its small end, with the large end reaching for the sky. And a bad egg will float. Fresh eggs will sink to the bottom of the bowl and lie on their sides. Slightly older eggs (about one week) will lie on the bottom but bob slightly. If the egg balances on its smallest end, with the large end reaching for the sky, it's probably around three weeks old. Eggs that float at the surface are bad and should not be eaten. When you buy eggs at the grocery store they have a date on the end of the carton that you need to pay attention to, if you do not think you will eat the eggs by the date on the carton, look for a better date on the other cartons.