The explosion of ChatGPT, Claude, and other large language models has created an unprecedented flood of AI-generated website content. By 2026, an estimated 30% of web content is at least partially AI-generated. Google's response has been decisive: the Helpful Content Update (and its successors) actively penalise sites that publish AI content without substantial human editing, expertise, or original insight.
The question isn't whether AI content will be detected — it's how quickly it will affect your rankings and trust score.
How AI Content Detection Works
Detection relies on statistical patterns that AI models consistently produce, even with prompting tricks:
Sentence-Length Uniformity
Human writers naturally vary their sentence length. A paragraph might have a 5-word sentence followed by a 25-word one. AI models produce remarkably consistent sentence lengths — the standard deviation tends to be low (under 3.0) compared to human writing (typically 5–12).
Trigram Lexical Diversity
A trigram is a sequence of three consecutive words. Human writing tends to have high trigram uniqueness — we use varied phrasing, idioms, and unexpected word combinations. AI text reuses similar trigram patterns more frequently, resulting in a lower uniqueness ratio (below 0.65, versus human averages of 0.70–0.95).
Other Signals
Perplexity scores, burstiness patterns, and vocabulary distribution also differ between human and AI text. Our scanner focuses on the two most reliable standalone heuristics: sentence-length standard deviation and trigram uniqueness.
Why Google Penalises AI Content
Google's E-E-A-T framework — Experience, Expertise, Authoritativeness, Trustworthiness — explicitly values first-hand experience and demonstrable expertise. AI-generated text, by definition, has neither. It produces confident-sounding text that can be factually wrong, generic, or disconnected from real-world practice.
The Helpful Content Update introduced a site-level classifier: if Google determines that a significant portion of your site's content exists primarily to manipulate search rankings rather than help users, it applies a penalty across all pages — not just the AI-generated ones.
What We Check and How to Interpret Results
When we detect likely AI-generated content, it appears as a medium-severity risk in your audit:
- Sentence StdDev below 3.0 — text is unusually uniform in structure
- Trigram uniqueness below 0.65 — vocabulary and phrasing lack natural variety
This doesn't mean your content is bad — it means it has statistical properties consistent with AI generation. If the content was AI-assisted but heavily human-edited, the flag may be a false positive. If it was published directly from a chatbot, it's a valid finding.
How to Fix AI Content Issues
1. Don't delete AI-assisted content — edit it. Add personal anecdotes, specific numbers from your experience, and unique insights that an AI model couldn't produce 2. Add author bylines with credentials (E-E-A-T signal) — "Written by [Name], [Role] with X years in [industry]" 3. Include original data — screenshots, case studies, proprietary research, or quotes from real interviews 4. Vary your sentence structure — break up paragraphs, use questions, add short punchy sentences between longer ones
Check your website's content quality at RoastReady — our scanner runs AI content detection alongside 50+ other trust signals.