What is the superlative form of FREE?

There isn't a superlative form of "free" in the traditional sense. Superlatives are used to compare three or more things, and "free" generally implies an absence of cost or restriction.

However, you can use other words to convey a similar meaning:

* Most liberating: This emphasizes the feeling of freedom.

* Utterly unrestricted: This emphasizes the lack of limitations.

* Completely unburdened: This emphasizes the absence of constraints.

The best choice depends on the context and what you want to emphasize.