when I am free, I am/will be

[lycen]

When I am free, I am able to help you.

When I am free, I will be able to help you.

Just want to clarify, am I right to say both is the same and correct?

 

[bhaisahab]

When I am free, I am able to help you.

When I am free, I will be able to help you.

Just want to clarify, am I right to say both is the same and correct?

They are both correct. They don't mean exactly the same though.
The first one means that, in general, whenever I am free I can help you.
The second has a future meaning: "when I am free, after I have finished what I am doing now, I will be able to help you.