The llms.txt Effect | Trakkr Research

A dated llms.txt adoption snapshot with separate subset and full-sample citation tests. Answer pages, reference facts, and live trackers drawn from this study.

Methodology: Derived from The llms.txt Effect and updated September 4, 2026.

What this hub contains

A dated llms.txt adoption snapshot with separate subset and full-sample citation tests. Answer pages, reference facts, and live trackers drawn from this study.

Answer Pages

Narrow questions answered directly from the study.

• Does llms.txt increase AI citations? - This snapshot does not establish a causal increase. The top-5,000 test returns p=0.85, while the full 37,894-domain sample returns p<0.001 with reported r=-0.065.
• How common is llms.txt on AI-cited domains? - It is still uncommon. Only 13.3% of the 37,894 scanned AI-cited domains had an llms.txt file.
• Is llms.txt more common on top domains than the long tail? - Somewhat, but not dramatically. Adoption reaches 16.1% in the top 5,000 cited domains, yet the top 50 sit at only 6.0%, which undercuts the idea that the strongest citation winners are relying on llms.txt.
• Which industries adopt llms.txt most? - SaaS and developer-heavy sites adopt llms.txt most aggressively. In the study, SaaS and developer tools reach 24.1% adoption, while government and academic sites sit at only 1.5%.
• Does llms.txt help you even if it does not raise citations? - This study does not test operational uses of llms.txt. It reports adoption and citation associations, with different results for the top-5,000 subset and the full sample.
• Should you prioritize llms.txt over answer infrastructure? - This study cannot rank those investments. It does not compare interventions or show that adding llms.txt causes more citations.
• Why is llms.txt getting so much attention if the effect is null? - The premise needs care: only the top-5,000 test is non-significant. The full-sample test is significant with a small reported effect size. The study does not measure why people adopt the file.
• Do the raw citation averages show any real advantage? - The published averages are 6.8 citations with llms.txt and 6.7 without it. These descriptive values alone do not establish practical importance, statistical significance, or a causal benefit.
• Is llms.txt a leading indicator of AI readiness? - Not reliably on its own. It is more common among technical, SaaS-heavy sites, but the study does not show that it predicts better citation outcomes by itself.
• What is the best way to read the null result? - Read p=0.85 as a non-significant test in the top 5,000 cited domains. The full sample returns p<0.001 with reported r=-0.065. Neither establishes that the causal effect is exactly zero.
• What should teams do after seeing the llms.txt data? - Use the snapshot to understand adoption and association. If you publish llms.txt for a specific workflow, measure that workflow directly and avoid promising a citation lift from this study.
• Does llms.txt look like a sector-specific behavior more than a universal standard? - Yes. Adoption is much higher in SaaS and developer tooling than in government, academic, review, or reference-heavy sectors, which makes it look more like a technical-community behavior than a universal web standard.

Reference Facts

Short, quotable claims with metrics and methodology context.

• llms.txt adoption is only 13.3% - Adoption is real, but still far from universal.
• Median citations are identical with and without llms.txt - Both published group medians equal 3 citations.
• Average citations are functionally flat with and without the file - The published group means differ by 0.1 citations.
• The top-5,000 test is not statistically significant - Only the top-5,000 subset test is non-significant; the full-sample test is significant.
• Top 5,000 domain adoption is still only 16.1% - Even the more visible end of the corpus is not overwhelmingly using llms.txt.
• Top 50 domain adoption is lower than the full corpus - The very top of the citation graph is not leaning on llms.txt.
• SaaS and developer sites adopt llms.txt far more often - The file is culturally concentrated among technical sites.
• Government and academic sites barely use llms.txt - Some of the web’s most authoritative sectors barely use the file.

Trackers

Live benchmark views built from the study’s most reusable dimensions.

• llms.txt adoption by citation tier - Adoption rate across different levels of citation prominence.
• llms.txt adoption by sector - Adoption skew across named industry groups in the Trakkr study.