# Ahrefs study: llms.txt files mostly unread by AI crawlers

Published: 2026-08-18T14:37:03.051Z · Source: Search Engine Journal (https://www.searchenginejournal.com/ai-search-myths-debunked-ahrefs-spa/584393/)
Source date: 2026-08-18
Flags: Ahrefs study — vendor-published
Entities: ahrefs, ai-overviews, llms-txt

An Ahrefs analysis spanning roughly 15 million data points found 97% of sites' llms.txt files were never read by AI crawlers and that adding schema markup produced no measurable lift in AI citations across 1,885 pages tested over 30 days, per Search Engine Journal. The same research found Google AI Overviews cut position-1 click-through rates by 58% in 2026, up from a 34.5% drop in 2025, while 88.46% of AI citations still traced back to pages in the general search index.

Why it matters: The findings undercut two of the most common AEO tactics, llms.txt and schema markup, while reinforcing that traditional search-ranking signals still drive most AI-answer citations.

## What this answers

**Does llms.txt help with AI search visibility?**

Not much — an Ahrefs analysis found AI crawlers never read 97% of sites' llms.txt files, echoing earlier Google guidance that the file does nothing for search.

**Do Google AI Overviews reduce click-through rates?**

Yes — Ahrefs found AI Overviews cut position-1 click-through rates by 58% in 2026, a bigger hit than the 34.5% drop it measured in 2025.

**Does adding schema markup increase AI citations?**

An Ahrefs test of 1,885 pages found adding schema markup produced no measurable increase in AI citations after 30 days.


Canonical: https://anythingengineoptimization.com/item/2026-08-18-ahrefs-study-llms-txt-files-mostly-unread-by-ai-crawlers/
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