Say the same thing a different way, without losing the meaning.
Rewording a source still uses the source's idea, and an idea needs a citation whether or not you kept the wording. Paraphrasing is for clarity — cutting inflated phrasing, shortening a tangled sentence, matching a house style. It is not a way to avoid attribution, and reviewers notice.
Standard, fluent, formal and simple. Standard keeps close to your structure; simple cuts hardest; formal raises the register.
That is the goal, but always read the output. Any rewriting tool can flatten a distinction you cared about.
No daily cap. Longer passages run on a server and are rate-limited rather than paywalled.