How Long Does a Chicken Egg Take to Hatch?

Hatching a chicken egg is mostly a humidity problem, not a temperature one — the last few days matter more than any other part of incubation. This guide draws on Mississippi State University Extension's poultry hatching guidance, and is general information rather than a substitute for direct incubator instructions.

About 21 days from setting

Chicken eggs take about 21 days to hatch. Extension guidance is specific: all chicks should be out of their shells by the end of day 21, and chicks that hatch after day 22 aren't usually as healthy and vigorous as those that hatch on time. Our hatch-date calculator shows the expected date from when you set the egg, alongside the normal day-20-to-22 range.

Humidity: low for most of incubation, high for the last 3 days

For the first 18 days, relative humidity should stay around 58–60% (85–87°F on a wet-bulb thermometer). For the last 3 days before hatching, it should rise to at least 65% (89–90°F wet bulb). Getting this wrong in either direction causes real problems: too much humidity throughout incubation stops eggs losing enough water by evaporation (roughly 12% of the egg's weight is meant to be lost this way), and a chick can actually drown in the fluid left in the shell at hatching. Too little humidity during the final days causes the opposite problem — the membranes inside the shell dry out and stick to the chick.

Don't open the incubator once hatching starts

Extension guidance is direct: don't open the incubator during the 3 days before hatching, or vital moisture is lost. Once a chick has pipped through the shell, membrane drying can happen within 1 to 2 minutes of the incubator being opened, stopping the chick from being able to turn and finish hatching. The safest approach is to leave the incubator closed until every chick has hatched and is ready for the brooder.

Pipped but not hatching: what actually goes wrong

A chick that has developed far enough to pip the shell is normally healthy enough to finish hatching on its own, unless something about the incubator environment stops it. The two documented causes are ventilation and humidity: restricting air vents near hatching to try to raise humidity backfires, since it suffocates the chick rather than helping it — vents should never be closed down to increase humidity. The other cause is the membrane-drying problem above, from opening the incubator at the wrong moment.

Removing chicks from the incubator

Once hatched, chicks are normally left in the incubator for 1 to 24 hours before being moved. The key test is whether a chick is dry, fluffy and walking well — a wet chick should stay put, since it chills quickly and can die soon after removal if taken out too early. If not every egg has hatched within 24 hours of the first chick, dry chicks should be removed and the rest checked again at 18-to-24-hour intervals, opening the incubator only briefly each time to limit moisture loss. Once chicks are dry and fluffed up, move them to a brooder with feed and fresh water ready.

After hatching

A newly hatched chick has no reserves for going without water, so fresh drinking water in the brooding area matters from the moment chicks arrive there. See our feed guide for the age-banded starter feed a chick needs from day one, and our health guide for what to watch for as chicks grow.

Source: Mississippi State University Extension Service, “Hatching Quality Chicks”, “Pipped Eggs That Do Not Hatch”, and “Chick Removal from Hatchery”: extension.msstate.edu. The same source already cited for this site's chicken incubation length. Sources checked: September 2026.

Common questions

How long does a chicken egg take to hatch?

About 21 days from setting. Mississippi State University Extension says all chicks should be out of their shells by the end of day 21, and chicks that hatch after day 22 aren't usually healthy and vigorous.

What humidity does a chicken egg need to hatch?

Extension guidance recommends 58-60% relative humidity (85-87°F wet bulb) for the first 18 days, raised to at least 65% (89-90°F wet bulb) for the last 3 days before hatching.

Why shouldn't you open the incubator near hatching?

Opening the incubator lets vital moisture escape. If humidity drops during hatching, the membranes inside the shell can dry and stick to the chick within 1 to 2 minutes, preventing it from turning and finishing the hatch.

When should you remove a chick from the incubator?

Once it's dry and fluffy and can walk well, usually 1 to 24 hours after hatching. A wet chick should stay in the incubator, since it chills quickly and can die soon after removal if taken out too early.