Precisely how long an egg takes to hatch depends on a lot of factors including species, breed, strain, conditions under which the egg was stored prior to incubation, and conditions during incubation. But whether you plan to hatch eggs in an incubator or under a hen you need a more definitive answer the question: How long does it take for an egg to hatch?
Basic Incubation Periods
- Bantam: 19-20 days
- Chicken: 21 days
- Duck (most breeds): 26-28 days
- Duck, Muscovy: 33-37 days
- Guinea Fowl: 26-28 days
- Goose (most breeds): 28-32 days
- Goose, Canadian & Egyptian: 33-37 days
- Turkey: 26-28 days
Eggs will take longer than usual to hatch if they are held for a while before being set, or are set in an incubator that runs on the slightly cool side. Eggs will hatch sooner than usual if the incubator is run slightly on the warm side.
In general, large chicken eggs — such as Jersey Giant eggs — take longer than 21 days by as much as 2 days. Smaller eggs — including those of most bantams — tend to hatch a day or two earlier than 21 days. Eggs of the Serama breed, smallest of all bantams, may hatch in 17 days or sometimes fewer.
Because the eggs of different breeds and species have different incubation periods, when combining eggs that you want to all hatch at the same time, schedule your settings accordingly. For example, bantam and White Leghorn eggs typically hatch a day early. So, when combining their eggs with those of other chicken breeds, add them to the incubator a day later than the other breeds.
Likewise, the eggs of bantam ducks and Khaki Campbells have a shorter incubation period than most other duck breeds. So, when hatching them along with other duck eggs, set them a day later. If you hatch both chickens and ducks, begin incubating the duck eggs a week before the chicken eggs.
The optimal temperature for hatching is 0.5 to 1°F cooler than for incubation, with humidity 6% to 10% higher. These conditions easily may be achieved when all the eggs are set in an incubator according to their incubation rates, so they all hatch together.
The same occurs automatically when eggs are hatched under a hen. However, when a hen starts setting on different eggs at the same time, she may leave the nest with the ones that hatch first, abandoning the rest. In that event, be prepared to gather up and brood the babies as they hatch. The hen may or may not accept the early hatchers back, depending on how long it’s been by the time the rest of the eggs hatch.
When different eggs are placed in an incubator at the same time, and therefore will hatch at different times, conditions must be averaged to accommodate the various stages of incubation. However, moving the about-to-hatch eggs to a separate hatcher results in a more successful hatch.
And that’s today’s news from the Cackle Coop.
Gail Damerow is the author of Hatching and Brooding Your Own Chicks: Chickens, Turkeys, Ducks, Geese, Guinea Fowl.