This Is the Easiest Way to Tell if Your Eggs Are Old

Say you've decided to whip up one of your favorite egg dishes. You open the fridge, pull out the egg carton, and it's time to get cracking! Ah, but then you see the expiration date was two days ago. Or two weeks ago. Do you give up that deliciously loaded scramble you were dreaming of?

But here's the thing: The dates on egg cartons are less than discernible. In some states, egg packagers are required to list sell-by dates. In others, they must stamp expiration dates. And neither date tells the whole story when it comes to freshness. That's because eggs can be and often still are perfectly good long after the date—any date—that's printed on the outside of the plastic or Styrofoam box.

If you find yourself wondering how long your eggs will last, follow this trick.

How to Check Your Egg’s Freshness

Even past their expiration date, chicken eggs are often still wholly safe to eat. But before you crack a single shell, there's a quick test you can do to get an idea of how fresh the egg is.

1. Fill a large bowl or tall glass with cold water.
2. Gently place the egg in the bowl or glass. If you're using a tall glass, consider sitting the egg on a spoon and gently lowering it into the water so it doesn't sink quickly and crack.
3. If the egg sinks and rests on its side, that is a very fresh egg. If it sinks but sits upright and bobs at the bottom of the bowl or cup, that egg is still fresh. It's just a bit older. Lastly, if the egg floats, that egg is no longer fresh.

Why Old Eggs Float

Egg shells are porous. As eggs sit and age, air moves into the egg as water evaporates. The older an egg is, the more air makes its way inside the shell. As the air pocket grows, the egg's likelihood to float increases.

An egg's quality does decline as it sits, too. The egg white, or albumen, gets thinner and more watery. Yolks lose some of their buoyancy.

You'll be able to see this in real-time if you crack a fresh egg beside an old egg on a flat surface. A fresh egg's yolk and white sit up taller while the older egg is flatter.

When in Doubt, Use the Smell Test

Even when an egg floats, it isn't necessarily bad. Indeed, old eggs can often be used in any application, from hard-boiled snacks to birthday cakes. Just consider a floating egg a warning to be extra attentive to the egg before you toss it into a pan or mixing bowl.

Use two of your best senses—sight and smell—to decide if an old egg really is bad. Eggs that are no longer good or safe to use produce a strong, distinct smell. (Fresh eggs have no smell, so if you smell anything when you take a sniff, it's likely a sign the egg is no longer good.)

Likewise, eggs that should be tossed in the trash may also show signs of mold or bacteria growth when you crack into them.

How to Properly Store Eggs

Despite their clever design, ceramic egg dishes or the plastic trays in refrigerator doors are not the ideal locations for storing your fresh eggs. (Same goes for milk.) Leave eggs in the carton you purchased them in to protect them from bacteria and cracking, and place them on an inside shelf. In a fridge door, they're more likely to crack with all the movement. Plus, temperatures on a fridge door are not consistent. You invite bacteria growth if you let your eggs warm and cool repeatedly.

Before you stash the carton in the fridge, take a moment to turn each egg so that the narrowed end is in the cup and the wider end is pointing up.

Each egg has a small air pocket on the broadest end of the egg. When you place the bigger end (with its air pocket) upward, you help slow moisture loss and the growth of the air pocket.