Here is a simple way to tell if your eggs are still fresh, whether you buy them from the grocery store, raise your own chickens for eggs or support a local farmer.
Materials
Glass Bowl or jar
Cold Water
Instructions
The Float Test
Fill a clear bowl or glass with enough cold water to fully submerge the egg and gently place it in the vessel.
Sinks and lies flat on its side - Very fresh.
Sinks but stands upright or tilts - Older (roughly a week or more) but usually still fine to eat; use soon.
Floats - Significantly older due to a large air cell. It may still be safe, but crack and check carefully before using (or discard if unsure).
Notes
Use plain cold water (salted water changes density and can skew results).