If you're a fan of eggs, maybe you've boiled them many times to eat as is or to make a dish such as devilled eggs. If the shells of your eggs have cracked on more than one occasion, causing the egg whites to ooze out and rendering the egg virtually useless -- you'll want to prevent this from happening again so you can have edible eggs on your plate instead of a mess in your pot.
Let the eggs sit out on the counter for 20 to 30 minutes before boiling. This allows the eggs to come down to room temperature, which decreases the chance of cracking from the swift change in temperature from the refrigerator to boiling water. If you don't have time to let refrigerated eggs sit at room temperature, carefully place them in the pot and pour cool or cold water over them. Bring the cold water to boil. This will take longer than hot water but will prevent cold eggs from cracking from the shock of sudden hot water.
Use an egg pricker to pierce a tiny hole into each egg if you have one. Egg prickers have a very tiny needle that pricks the egg when you place it on the base. The hole is so tiny that no egg contents can leak out, but air is able to escape from the hole, which prevents cracking while it is boiling.
Add 1/2 tsp salt and 1 tbsp of vinegar to the boiling water. The salt is believed to help prevent cracking and also to make the eggs easier to peel. The vinegar keeps the egg whites from leaking out of any eggs that do end up cracking.
Simmer the eggs instead of having them boil over high heat. Eggs can be tossed around roughly in highly boiling water, which can cause the eggs to crack as well. As well, do not overboil the eggs. If you leave the eggs to boil for too long, they will begin to crack from all of the built-up pressure inside. A hard-boiled egg should not be cooked for longer than 10 minutes on a full boil. For soft-boiled eggs, boil the eggs for no more than three minutes.
Place the eggs in an ice bath immediately after they are done cooking to stop the cooking process and to make them easier to peel.