How old when they first molt?

[Bee]

Im not entirely sure how old my budgie is and i've never seen him molt. How old are they on average for their first molt? And what exactly does it look like? They just lose feathers and grow new ones?

[Smoothy]

It's usually 4-6 months when they go through their first molt and can last weeks sometimes months. When they begin to molt their older feathers will be darker and greasier in color and their bars will begin to disappear from ontop of their head. Once they have molted the top of their head will look as if they've slicked their hair back which will either be yellow or white with no bars on them. After the molt they will have a cleaner more clear outer body, the bars on their body will be more visible.
But mainly look for the clear, no bars look on his head which will be clear yellow or white. It extends back a little bit more than as if its just sticking up.