Pictures for reference

[ChickenMamii]

It's been about a month since I've bought my chicks. I'd really like to know when is the best time to move them into their coop outside. Can someone share a photo of how big they should be? Thanks in advance First time chicken owner so open to advice.

 

[nuthatched]

It's not a matter of size, but readiness. What are your temperatures?
Are they off heat? How feathered are they?