Web Almanac: two sites in a hundred have llms.txt
The SEO chapter of Web Almanac 2025 counted llms.txt across the HTTP Archive crawl for the first time - 2.1% of sites, and most files come from WordPress plugins
Web Almanac is a yearly report on the state of the web built on the HTTP Archive crawl. Its SEO chapter for 2025, published on January 15, 2026, counted llms.txt files for the first time.
What was measured
The HTTP Archive crawl requests the home pages of millions of sites. For each site the authors checked whether /llms.txt answers.
| Measure | Value |
|---|---|
| Sites with the file, desktop sample | 2.13% |
| Sites with the file, mobile sample | 2.10% |
| Files found | 324,184 |
| Created by the All in One SEO plugin | 39.6% |
| Created by the Yoast SEO plugin | 3.6% |
What follows
Two percent is the most sober estimate available. It comes from a broad crawl, not from a sample of sites whose owners work on promotion. In such samples the share is several times higher: Ahrefs got 28% and called it an upper bound.
The second finding matters more than the first. Almost half of the files were created by two WordPress plugins. A file appears not because the owner decided to write it, but because the feature is switched on in a plugin.
What the report does not show
- Who reads these files. It counts presence, not requests.
- How good the files are. The content was not analyzed; Common Crawl did that later.
- What happens below the home page: files in subpaths were not counted.
What a site owner should do
If the site runs on WordPress, check whether a plugin has published a file without your knowledge and what it says: llms.txt in WordPress. All adoption estimates, with an explanation of why they differ: Who publishes llms.txt.