There isn’t a universal “safe” percentage for AI-generated text. What matters is the policy of the platform, school, publisher, or employer , because some allow heavy AI assistance while others require disclosure or almost entirely human-written work.

Practical rule of thumb

  • For casual posts or internal drafts , AI can be fine as long as you edit heavily and keep the final voice human.
  • For school, journalism, publishing, or public-interest writing , even a small amount of AI text may need to be disclosed, and some places may reject it outright.
  • For SEO/content marketing , many teams use AI routinely, but quality, originality, and usefulness matter more than a percentage number.

A useful way to think about it

Instead of asking “What percent is okay?”, ask:

  1. Is AI allowed here?
  2. Do I need to disclose it?
  3. Does the final text sound like me or just polished machine output?
  4. Would I be comfortable explaining how much I used?

That last point matters because students and writers often feel something personal is lost when AI does too much of the writing.

Rough guideline

If you want a simple, practical answer:

  • 0–20% : usually low concern in many informal settings.
  • 20–50% : medium risk; often okay only if disclosed or clearly edited.
  • 50%+ : likely to be seen as AI-assisted rather than human-authored, and may trigger rules or scrutiny.

Best practice

Use AI for brainstorming, outlines, rewrites, or grammar help, then rewrite the final version yourself. If this is for school, work, or publication, check the exact rule first, because “fine” depends more on context than on the percentage itself.

TL;DR: There’s no single acceptable percentage; the safest standard is to follow the specific rule where you’re publishing, and disclose AI use when required.