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llms.txt GeneratorIs 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.
The key numbers.
- Top 5k adoption
- Adoption among the top 5,000 cited domains.
- 16.1%
- Top 50 adoption
- Adoption among the top 50 cited domains.
- 6.0%
- Adoption rate
- Domains with llms.txt in the study.
- 13.3%
The adoption curve is mixed and does not line up neatly with citation leadership.
The evidence.
Source
The llms.txt Effect
| Measure | Result |
|---|---|
| Top 5k adoption Adoption among the top 5,000 cited domains. | 16.1% |
| Top 50 adoption Adoption among the top 50 cited domains. | 6.0% |
| Adoption rate Domains with llms.txt in the study. | 13.3% |
Population and method
Built from HTTP scans of 37,894 AI-cited domains, linked to 337,362 citations and 882 citation snapshots in the Trakkr corpus.
Where the evidence stops
This is an observational study. It measures correlation with citation outcomes, not a controlled experiment.
Adoption is uneven by sector, so raw averages can hide category concentration in SaaS and developer tooling.
The top-5,000 test returns p=0.85. The full scanned sample returns p<0.001 with reported r=-0.065. Neither establishes a causal effect. The public aggregates do not include confidence intervals or document the cohort for citation means and medians well enough to recompute the tests.
What to do with this
- Treat llms.txt as an optional housekeeping file, not a primary citation-growth lever.
- Prioritize answer quality, source coverage, and page structure before spending disproportionate effort on llms.txt.
- If you do publish llms.txt, measure discovery and crawl behavior directly instead of assuming it improved citation performance.
This answer matters because it turns a study finding into an operating rule teams can use when they decide what to publish, refresh, or measure next.
Questions about this answer.
Cite this answer.
Source study: llms.txt Effect“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.”
Mack Grenfell · Is llms.txt more common on top domains than the long tail?
The llms.txt Effect · Trakkr Research · Updated 4 September 2026