llms.txt Registry· updated 7 October 2026
We checked 1,000,642 websites for llms.txt. Here's what we found.
96% have nothing. More sites block us than publish one. Every figure here is a count from domains we have actually probed. Nothing is extrapolated.
Wondering whether any of this matters? Does llms.txt work? weighs every study we could find, for and against.
1,000,642
domains checked
0 since 13 September 2026
37,160
publish an llms.txt
−39794 since 13 September 2026
3.66%
adoption
−3.98 points since 13 September 2026
Adoption is measured over 999,839 domains drawn from a ranked list of the web, of which 36,599 publish a file. It deliberately excludes our examples directory and domains people chose to audit — both are populations selected because they were likely to have one, and counting them would inflate the figure several-fold.
How the registry has grown
One point per day since 13 September 2026, recorded by the scanner as it ran. Hover a line for the day's count.
Domains checked
1,000,642
llms.txt files found
37,161
Adoption, ranked sample
3.66%
Show as a table
| Day | Checked | Files | Adoption | Blocked |
|---|---|---|---|---|
| 2026-09-13 | 1,000,642 | 76,955 | 7.64% | 60,844 |
| 2026-09-14 | 1,000,642 | 78,071 | 7.75% | 62,914 |
| 2026-09-15 | 1,000,642 | 78,913 | 7.83% | 63,582 |
| 2026-09-16 | 1,000,642 | 79,063 | 7.85% | 63,715 |
| 2026-09-17 | 1,000,642 | 69,423 | 6.88% | 64,445 |
| 2026-09-18 | 1,000,642 | 62,865 | 6.23% | 65,203 |
| 2026-09-19 | 1,000,642 | 52,185 | 5.16% | 65,393 |
| 2026-09-20 | 1,000,642 | 47,204 | 4.66% | 66,387 |
| 2026-09-21 | 1,000,642 | 45,727 | 4.51% | 66,609 |
| 2026-09-22 | 1,000,642 | 44,730 | 4.41% | 66,834 |
| 2026-09-23 | 1,000,642 | 45,044 | 4.45% | 67,024 |
| 2026-09-24 | 1,000,642 | 49,788 | 4.92% | 60,884 |
| 2026-09-25 | 1,000,642 | 51,214 | 5.06% | 58,056 |
| 2026-09-26 | 1,000,642 | 50,261 | 5.02% | 52,610 |
| 2026-09-27 | 1,000,642 | 50,291 | 5.03% | 49,571 |
| 2026-09-28 | 1,000,642 | 47,927 | 4.79% | 50,571 |
| 2026-09-29 | 1,000,642 | 46,622 | 4.66% | 49,776 |
| 2026-09-30 | 1,000,642 | 44,403 | 4.44% | 49,641 |
| 2026-10-01 | 1,000,642 | 41,582 | 4.16% | 50,346 |
| 2026-10-02 | 1,000,642 | 42,336 | 4.23% | 51,100 |
| 2026-10-03 | 1,000,642 | 40,634 | 4.02% | 52,006 |
| 2026-10-04 | 1,000,642 | 41,975 | 4.15% | 53,222 |
| 2026-10-05 | 1,000,642 | 42,359 | 4.19% | 53,205 |
| 2026-10-06 | 1,000,642 | 38,698 | 3.81% | 53,317 |
| 2026-10-07 | 1,000,642 | 37,161 | 3.66% | 53,247 |
llms.txt files known, by the day we first saw them
37,160
This is when we found each file, not when it was published. A file met on a domain's first probe may have been there for years.
What we found
- Refusing our request
- 53,247
- Spec-valid files
- 15,062
- Invalid implementations
- 21,367
- Median linked URLs
- 5
- New files, last 30 days
- 0
- Changed, last 30 days
- 3,750
- Versions recorded
- 109,744
- Observing for
- 46 days
Nearly half return a 404.
What each domain's /llms.txt returned when we asked.
Show as a table
| Status | Domains | Share |
|---|---|---|
| missing | 449,954 | 45.0% |
| timeout | 349,933 | 35.0% |
| redirected | 55,404 | 5.5% |
| error | 54,944 | 5.5% |
| blocked | 53,247 | 5.3% |
| present | 37,160 | 3.7% |
"Unreachable" and "blocked" are counted separately from "not found", because a domain we could not read is not evidence that it has no file.
How big the files are
Every llms.txt we hold, by size. Our read-cost benchmark found roughly 40 KB (about 10,000 tokens) is where a file stops helping an agent and starts costing more than the site itself. Bands past that line are in red.
Show as a table
| Size | Files | Share |
|---|---|---|
| under 1KB | 2,539 | 7.1% |
| 1-10KB | 25,239 | 70.4% |
| 10-40KB | 4,167 | 11.6% |
| 40-100KB | 1,504 | 4.2% |
| over 100KB | 2,420 | 6.7% |
Adoption by top-level domain
Only TLDs with at least 200 checked domains are shown. Counts, not estimates.
Show as a table
| TLD | Adoption | Present | Checked |
|---|---|---|---|
| .pk | 18.2% | 157 | 861 |
| .ai | 12.2% | 426 | 3,502 |
| .ro | 7.8% | 317 | 4,046 |
| .in | 7.6% | 633 | 8,312 |
| .co | 7.3% | 407 | 5,588 |
| .cl | 7.1% | 179 | 2,504 |
| .sa | 7.1% | 16 | 226 |
| .ie | 6.3% | 87 | 1,377 |
| .store | 6.2% | 104 | 1,676 |
| .io | 5.8% | 585 | 10,056 |
| .ng | 5.8% | 14 | 241 |
| .mx | 5.7% | 80 | 1,396 |
| .ae | 5.7% | 34 | 599 |
| .ca | 5.6% | 310 | 5,536 |
| .pe | 5.3% | 27 | 506 |
llms-full.txt among adopters
Of 11,913 sites with an llms.txt that we also asked for an llms-full.txt, 5,230 publish one(43.9%).
Show as a table
| Size | Files | Share |
|---|---|---|
| under 1KB | 130 | 2.6% |
| 1-10KB | 4,410 | 86.6% |
| 10-40KB | 250 | 4.9% |
| 40-100KB | 84 | 1.6% |
| over 100KB | 219 | 4.3% |
A full-text file is read whole. On our benchmark, every llms-full.txt we met was larger than the site it described.
Cite this
llmstxt.studio llms.txt Registry, 7 October 2026. 1,000,642 domains checked; 3.66% of 999,839 ranked domains publish an llms.txt. https://llmstxt.studio/stats
Our figure is measured independently of anyone else's. For comparison, Rankability's monthly count over the Tranco top 1,000 and top 10,000 lands in the same range (their data). Where the two disagree, the sample sizes explain it.