When the pressure becomes too great, the gases escape by cracking weak points in the porous shell. Bringing eggs to room temperature before cooking slows down that process.
[header] How to cook hard boiled eggs without cracking [title] Bring your eggs to room temperature before cooking. [step] If you keep your eggs in the refrigerator, it's important that you don't try to cook them cold. Eggs crack because gases heat and expand within the shell.