{
  "kind": "fact",
  "studySlug": "llmstxt-effect",
  "slug": "llms-txt-adoption-is-only-thirteen-point-three-percent",
  "title": "llms.txt adoption is only 13.3%",
  "description": "Adoption is real, but still far from universal.",
  "lastUpdated": "2026-09-04",
  "lastTested": "2026-03-14",
  "sourceStudyUrl": "/trakkr-research/llmstxt-effect",
  "sourceStudyTitle": "The llms.txt Effect",
  "claimIds": [
    "llmstxt-effect:adoption",
    "llmstxt-effect:domains"
  ],
  "relatedSlugs": [
    "answer:does-llms-txt-increase-ai-citations",
    "answer:how-common-is-llms-txt-on-ai-cited-domains",
    "tracker:llmstxt-adoption-by-tier-tracker"
  ],
  "methodologySummary": "Built from HTTP scans of 37,894 AI-cited domains, linked to 337,362 citations and 882 citation snapshots in the Trakkr corpus.",
  "limitations": [
    "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."
  ],
  "keywords": [
    "llms.txt",
    "llms txt effect",
    "AI citations",
    "does llms.txt work"
  ],
  "schemaHints": {
    "pageType": "Article",
    "includeDataset": true
  },
  "claim": "Only 13.3% of scanned AI-cited domains had an llms.txt file in the Trakkr study.",
  "supportingMetrics": [
    {
      "label": "Adoption rate",
      "value": "13.3%",
      "detail": "Domains with llms.txt in the study."
    },
    {
      "label": "Domains scanned",
      "value": "37,894",
      "detail": "AI-cited domains scanned for llms.txt."
    }
  ],
  "whyItMatters": "This is not yet a web-wide standard that citation winners consistently depend on.",
  "citationBlock": {
    "quote": "Only 13.3% of scanned AI-cited domains had an llms.txt file in the Trakkr study.",
    "attribution": "The llms.txt Effect - Trakkr Research",
    "url": "https://trakkr.ai/trakkr-research/llmstxt-effect/facts/llms-txt-adoption-is-only-thirteen-point-three-percent"
  }
}