How to Tell If a Boiled Egg Has Gone Bad

2. Notice Any Unusual Smell During Boiling

When boiling eggs, pay attention to the smell of the water. Fresh eggs have a mild scent, even when cooked. However, if you notice a strong, unpleasant, or sulfur-like odor while boiling, that may be a warning sign.

Sometimes eggs release a slight sulfur smell when overcooked, which is normal. But if the smell is sharp, rotten, or overwhelmingly foul, it’s best to throw the eggs away immediately.

If a shell cracks open during boiling and releases a bad smell, that egg is likely spoiled.