Breed differences

[Kandypeeps05]

do some chicken breeds take longer to hatch or are all chickens on the 21 days

 

[NatJ]

21 days is considered normal for all breeds.

Any breed can hatch a day or two early or late.
If you have an incubator that is just a little too warm or too cool, that can also cause hatching to be a day off one way or the other.

I have read that some bantams hatch about 2 days earlier than other chickens, but I have also read that bantams do not hatch early, so I'm not quite sure what to think about that.