What age are chicks grown up?

[Rachy]

I have 3 Pekin bantams. Two are 9 weeks old and one is 13 weeks old and she is clucking, the other two still cheeping.

What age are they fully grown, or stop growing? I actually want to order a chicken nappy and wondering how old she needs to be before measuring her up but also wondering when they are officially 'grown ups'!

 

[HEChicken]

They grow very quickly for the first 5-6 months and attain most of their size in that time. However they can continue to grow slowly from 6 months until they finally stop at around 12 months of age.

 

[Rachy]

Thank you, longer that I thought. Much appreciated

Bit of a 'guesstimate' needed I think