• AI visibility

Guide · AI search

Does readable writing help your content appear in AI answers?

Somewhat, but it is not a lever on its own. AI search engines tend to cite easier-to-read pages, and early lab tests found that smoother writing raised a page’s share of an answer. Later, larger tests found that polishing wording rarely changes whether a page is cited, so readability works best as part of genuinely useful content.

By Underneath Team Guide Updated

The short version

  1. In the first lab study of AI search optimization, making a source more fluent and easier to understand raised its visibility by 15 to 30% (Aggarwal and colleagues (opens in a new tab)).
  2. Across 55,936 searches, pages cited by AI search engines had a reading ease score of 24.15, against 12.32 for pages from Google and Bing (Zhang and colleagues (opens in a new tab)).
  3. A later benchmark tested ten rewriting methods, including fluency and simpler language, and found real gains in only three of 54 cases (Puerto and colleagues (opens in a new tab)).
  4. In a shopping test, a fluency rewrite moved Amazon listings down by 0.40 places on average in Claude’s rankings (Bagga and colleagues (opens in a new tab)).
  5. One end-to-end test found rewriting page text for AI engines cut final citations by 6%, and rewritten pages were also found less often (Martinez (opens in a new tab)).

What did the first lab test find about fluent writing?

It found a clear lift, in a controlled setting. In the 2023 study that named generative engine optimization, researchers rewrote web sources in several ways. They then measured how much of an AI answer each source accounted for (Aggarwal and colleagues (opens in a new tab)).

Two of the rewrites were about style rather than substance. One improved fluency; the other simplified the language. These style changes raised visibility by 15 to 30%.

Fluency also combined well: pairing it with added statistics beat any single method by more than 5.5%. Whether added statistics hold up on their own is covered in our guide to statistics, quotes and citations.

The setup matters. The engine was built by the researchers on GPT-3.5, and only the top 5 Google results were placed in front of it for each question. So the test shows what happens once a page is already in the AI engine’s hands, not whether better writing gets it found.

A later study still found fluency the strongest of these original methods (Wu and colleagues (opens in a new tab)). Rules learned from each engine beat it by up to 50.99%.

Do AI engines cite easier-to-read pages in the real world?

Yes, on average they do. A team at the Hong Kong University of Science and Technology and Rutgers compared sources from six AI search engines with Google and Bing results (Zhang and colleagues (opens in a new tab)). They used 55,936 searches built from trending topics in July and August 2025.

They sampled 10,000 web addresses from each group and scored the text with two standard reading measures. Reading ease runs from hard to easy; grade level estimates the years of schooling a reader needs.

Reading measurePages from Google and BingPages cited by AI engines
Reading ease (higher is easier)12.3224.15
Grade level (lower is easier)18.2414.57

Both groups score as hard reading, but the AI-cited pages were noticeably easier. The authors say AI engines “tend to favor more accessible, less textually demanding content.” This compares two groups of pages; it does not show that easier writing caused any citation. Our study of pages cited by AI Overviews compared pages on the same search instead.

Why did later experiments find polishing text does little?

Because when researchers measured which source an AI engine cites first, style edits rarely moved it. C-SEO Bench, a test across six kinds of content, applied ten methods, including fluency and simpler language, to one page at a time (Puerto and colleagues (opens in a new tab)).

Out of 54 combinations of method and content type, only three produced a reliable improvement, and none of those were fluency or simpler language. Many methods pushed pages down. The authors note the earlier lift was measured by how many words an answer devoted to a source, which is not the same as being cited first.

A shopping test found the same. Researchers rewrote Amazon product listings with 15 instructions and measured how far each moved in five AI engines’ rankings (Bagga and colleagues (opens in a new tab)).

The fluency rewrite did worse than a plain rewrite. It moved listings down by 0.40 places on average in Claude’s rankings and by 0.21 places in GPT-5’s.

A third test, run by researchers at the software company Sprinklr, compared dense paragraphs with organized sections across 252,000 trials on six AI models. Layout alone had no consistent effect (Vishwakarma and colleagues (opens in a new tab)).

Is readability the cause, or a sign of something else?

Most likely a sign of something else. The studies cannot separate clear writing from the qualities that usually come with it, such as focus, accuracy and usefulness.

In a study of 18,151 pages cited by ChatGPT, Google and Perplexity, an AI model rated the quality of each page (Zhang Kai and colleagues (opens in a new tab)). The pages answers drew on most scored about 1.49 times higher than those drawn on least. Relevance to the question was the strongest signal they found, ahead of length or layout.

The Wu study shows what the engines seem to reward. Gemini, GPT and Claude each favored clear, concise language, but alongside comprehensive coverage, accurate facts, specific evidence and a conclusion stated up front (Wu and colleagues (opens in a new tab)). Readability sits inside a broader picture of a page that answers the question well. How far the three engines agree is covered in our guide on whether engines prefer the same content.

Can rewriting for AI engines backfire?

Yes. A rewrite can help a page once it is in front of the AI engine, yet make it harder to find in the first place.

A 2026 survey of 45 studies describes one end-to-end test (Martinez (opens in a new tab)). There, rewriting page text for AI engines made pages reach the top results less often and cut final citations by 6%.

The C-SEO Bench authors also found that gains shrink as more sites adopt the same method, so any edge from a style trick fades. The survey’s conclusion is that general rules of thumb “transfer poorly” between engines and settings.

What should you do about it?

Write clearly for people, and treat that as a baseline rather than a growth tactic.

  1. Edit for plain, readable language. AI-cited pages read more easily on average, and clear writing serves human readers too.
  2. Do not run pages through generic AI rewriters to make them “more fluent”. Controlled tests found little gain and some losses.
  3. Put the substance first: a direct answer, specific figures, definitions and comparisons. Those are what the engines appear to draw on.
  4. Protect what makes the page findable. Keep the terms people search for when you simplify, because a rewrite that loses them can cost you citations. Keeping terms is not the same as repeating them; see our guide to keyword stuffing in AI search.
  5. Test changes on a few pages before rolling them out, and check citations in each engine you care about.

If you want help making your pages both readable and useful to AI answers, see our generative engine optimization service.

What does the research not tell us yet?

No study has shown that rewriting a live page for readability raises its citations in real AI search.

  • The 15 to 30% lift came from a 2023 test with older models and a fixed set of five sources per question.
  • The reading ease gap compares groups of pages. It cannot separate readability from topic, site or quality.
  • The benchmarks tested rewrites made by AI models, not careful human editing.
  • Most tests used English content. Effects in other languages are unknown.
  • Nobody has measured whether readable pages turn AI visibility into more clicks or sales.

Frequently asked questions

Does simple language help with AI search?

Slightly, at best. AI-cited pages scored 24.15 on reading ease against 12.32 for Google and Bing pages, but tests that simplified pages found no reliable gain in citations.

Should we rewrite our content to be more fluent for ChatGPT?

Not as a tactic on its own. In a benchmark of 54 method and content combinations, only three produced reliable gains, and fluency was not among them.

What reading level do AI-cited pages have?

Fairly high. In a sample of 10,000 AI-cited pages, the average grade level was 14.57, against 18.24 for pages from Google and Bing.

Did the original GEO study find that readability matters?

Yes, in its setting. Fluency and simpler language raised visibility by 15 to 30%, but only for sources already handed to the AI engine.

Sources

Free strategy call

Some questions are easier to answer about your own business.

Bring the one that matters most. On a free 30-minute call we’ll take a first look at it and send you a short written read afterward.

Ask about my businessHow we work