Chicken eggs typically need to be incubated for about 21 days to hatch

. The incubation period can vary slightly, generally ranging from 20 to 21 days, with some chicks hatching a day or two early or late depending on conditions and egg storage time

. Key points for incubation include:

• Maintain a temperature around 99-102°F (37.2-38.9°C)

• Turn the eggs 3 to 5 times daily for the first 18 days to prevent the embryo from sticking to the shell

• Stop turning the eggs on day 18 and increase humidity to about 65-70% to prepare for hatching

• Chicks usually start hatching on day 21 but can take up to 24 hours to fully emerge

• If eggs were stored before incubation, additional time may be needed (about 1 hour more incubation per day of storage over 5 days)

In summary, incubate fertilized chicken eggs for 21 days under proper temperature and humidity conditions, turning them regularly until day 18, then allow chicks to hatch naturally around day 21