The standard method for boiling eggs typically requires about 6-7 minutes for a hard-boiled egg and 3-4 minutes for a soft-boiled egg. The duration varies depending on the desired level of doneness and the size of the eggs. Hard-boiled eggs are fully cooked and have a solid white and yolk, while soft-boiled eggs have a runny yolk. The cooking time is influenced by the temperature of the water and the initial temperature of the eggs. According to the United States Department of Agriculture (USDA), hard-boiled eggs should be cooked at a rolling boil for 6-7 minutes for large eggs, and soft-boiled eggs should be cooked at a gentle boil for 3-4 minutes.

The reason for these specific times lies in the science of heat transfer and the physical properties of eggs. When eggs are placed in boiling water, the heat causes the proteins in the egg white to coagulate and the yolk to solidify. The cooking time is crucial because it determines the extent of these changes. If the eggs are cooked for too long, the proteins can become tough and the yolk may become rubbery. Conversely, if the eggs are not cooked long enough, the proteins may not fully coagulate, resulting in a runny yolk or a soft white. The USDA's recommended cooking times are based on extensive research and testing to ensure the safety and quality of the eggs. It is also important to note that the cooking time can vary slightly depending on the altitude and the specific type of stove used.