What is the 30% rule for AI?

The 30 percent rule for AI is an informal editing guideline: let AI produce no more than about 30 percent of a finished text, and keep the remaining 70 percent human.

Some people flip the label and call it the 70/30 rule in AI. Either way, it is not a Google policy. Google measures quality and originality, not what percentage of a page a model wrote.

The rule survives because it works as a habit. AI handles outlines and first drafts, humans add facts, experience, and voice. Pages built that way avoid the repetitive phrasing that readers and spam systems both catch. Skip the human pass and the patterns pile up fast.

A tool that can humanize AI text for SEO does that pass automatically when drafts lean too robotic.