The egg-float test is a simple method you can use to determine the freshness of your eggs. Simply fill your glass about ½ to ⅔ full, then gently drop your egg into the water.

If the egg floats, it’s older, but if it sinks and lays flat, then it’s fresh. If it sinks to the bottom but tilts upwards, then it is less fresh than an egg that lays on its side.

The float test can be a great trick for recipes that benefit from fresh or older eggs. Poached eggs require fresher eggs, while hard-boiled eggs are better when they’re less fresh.

This trick works because as eggs age, the air pocket inside them expands, making them more buoyant. Other signs of spoilage include a bad odor or an unusual color.

If your egg has a crack in its shell or has a pink or pearlescent egg white, discard it immediately as the chances of it being infected with harmful microbes and bacteria are high.