Black australorp roo or hen

[Nenad]

This is my only black australorp chick. 5 month old. Is it hen or roo?

 

[DobieLover]

This is my only black australorp chick. 5 month old. Is it hen or roo?

If you could put it down and get some better side profile pictures that would help.
At 5 months old, it's not a chick, hen or roo. You've got either a cockerel or pullet. If you haven't heard crowing by now, I'm guessing she's a pullet.
At that age, you will see gender specific feathers in the saddle and hackle feathers. The cockerels will have long pointed feathers forming and the pullets will have rounded short feathers.
Long pointed cockerel saddle feathers indicated by the blue line.
Rounded pullet saddle feathers indicated by the pink line.

 

[Acre4Me]

I’m possibly seeing saddle feathers, but cannot see your pic very well. However, the comb and wattles are smaller than expected for 5 months, if it is a male. Try to get the chicken to stand and take pic from the side while chicken is standing. That way we can feathering much better.

 

[Rhodebar Lover]

I'm suspicious... Can you get saddle pictures?

 

[MysteryChicken]

Better pictures please?

 

[Nenad]

It grows slow I guess. Here are better pictures.

 

[roonster]

i say hen. austrolorp hens get pretty good wattles and comb.

 

[Nenad]

i say hen. austrolorp hens get pretty good wattles and comb.

I hope, thanks.

 

[Rhodebar Lover]

I'm going with cockerel but definitely update in a few weeks! Tricky bird

 

[MysteryChicken]

Looks pretty small for 5 months, thinking most likely 3.5 months.

I'm thinking late bloomer cockerel.