---
title: "\"llms.txt 擬似応答率\" (llms.txt pseudo-response rate): 8.1% of top .jp sites on 9 November 2026, and how it is counted | Parallel World - migurei"
description: "The llms.txt pseudo-response rate (llms.txt 擬似応答率) is the share of sites that answer /llms.txt with HTTP 200 but have no real llms.txt, usually an HTML soft 404. Top .jp sites: 8.9% on 26 October, 8.4% on 2 November, 8.1% on 9 November 2026 (a real file: 3.7%, 3.8%, 3.9%). The counting rule, and what it does not show."
lang: "en"
url: "https://pw.migurei.ai/en/research/llms-txt-pseudo-response-rate"
---

# "llms.txt 擬似応答率" (llms.txt pseudo-response rate): 8.1% of top .jp sites on 9 November 2026, and how it is counted

The llms.txt 擬似応答率 (llms.txt pseudo-response rate) is the share of sites asked for /llms.txt that answered HTTP 200 but had no real llms.txt file, in most cases an HTML page, a "soft 404". In our weekly scan of 9 November 2026 it was 63 of 775 top .jp sites, 8.1%. In the same week 30 sites (3.9%) had a real file.

Published 15 November 2026. Numbers taken on 26 October, 2 November and 9 November 2026. "Pseudo-response rate" (擬似応答率) is our own name for this way of counting, not an industry term. llms.txt is a proposed text file at the root of a site that gives AI apps a short guide to its content; it is a proposal, not a standard.

## What is the llms.txt 擬似応答率?

- **Definition:** the llms.txt 擬似応答率 is the share of sites asked for /llms.txt that answered HTTP 200 but had no real llms.txt.
- **A soft 404** is a server answering 200 with a page for an address that has nothing at it, instead of 404. The page "works"; the thing asked for is not there.
- **A real llms.txt** is an answer that meets all four: HTTP 200; `Content-Type` `text/plain` or `text/markdown`; a body that is not empty and does not open with an HTML tag; and an answer that ends at /llms.txt on the site's own registrable domain.
- **A pseudo-response** is an HTTP 200 answer that does not meet them: a `text/html` page, an empty body, a redirect to a home page.

## How it is counted

llms.txt 擬似応答率 = sites with a pseudo-response ÷ sites we could check

- **Denominator:** sites asked once for /llms.txt, leaving out those whose robots.txt was served by another registrable domain and those whose /llms.txt request ended on another one: 775 to 782 sites per week.
- **Numerator:** among them, sites that answered HTTP 200 and not with a real llms.txt. Other statuses, such as 404, do not count.
- **Population:** the first 1,000 top .jp domains of the Tranco list (a public ranking of the most visited domains). Our scanner identifies itself and asks each site once, every Monday, from a Japanese IP. No site is named.
- Counted by status code alone, the week of 26 October 2026 shows 98 sites (12.6%) as having the file: about 3.4 times the 29 real files. The pseudo-response rate makes that gap visible.

## The numbers (three weeks)

| Scan day | Sites checked | Pseudo-response (llms.txt 擬似応答率) | Real file | Pseudo-responses per real file |
| --- | --- | --- | --- | --- |
| 2026-10-26 | 777 | 69 (8.9%) | 29 (3.7%) | 2.4 |
| 2026-11-02 | 782 | 66 (8.4%) | 30 (3.8%) | 2.2 |
| 2026-11-09 | 775 | 63 (8.1%) | 30 (3.9%) | 2.1 |

- All 69 sites of 26 October 2026 answered `text/html`.
- The rate slipped from 8.9% to 8.4% to 8.1%, but three readings do not make a trend.
- The real count hardly moved: 29, 30, 30.

## Check your own site

1. Open `your-domain/llms.txt` in a browser.
2. Run `curl -I https://your-domain/llms.txt` and read the status and the `Content-Type`.
3. If you have no file and still get 200 and `text/html`, your site gives a pseudo-response. Change the server or site builder so that unknown addresses return 404.
4. The free check reads the file itself, not only the status: [https://pw.migurei.ai/en/free-scan](https://pw.migurei.ai/en/free-scan)

## Basis and limits

- **"Pseudo-response rate" is our own name.** It is not an industry term, and we do not know whether other surveys count this way.
- **Top .jp sites only.** About 780 of the first 1,000, one list, as seen from our scanner. Other sites may differ.
- **We do not know why the sites answer 200.** We have not looked at their servers.
- **Our filter does not check syntax.** A file served as plain text with wrong contents counts as real; a real file served with an odd `Content-Type` counts as a pseudo-response.
- **Whether any AI app reads llms.txt** is a separate question; this number does not show it.
- Source: the same rows of our weekly published CSV (the "llms.txt present" and "llms.txt answered 200 with something that is not the file" rows): [https://pw.migurei.ai/data/japanese-sites-and-ai-bots/2026-W46.csv](https://pw.migurei.ai/data/japanese-sites-and-ai-bots/2026-W46.csv) . Level: observed in our lab.
- Next: the scan continues every Monday; the next numbers are those of 16 November 2026.

## Related pages

- Three weeks in full, and the gap against counting by status code: [llms.txt on top .jp sites: real files and HTML soft 404s](https://pw.migurei.ai/en/research/jp-sites-llms-txt-html-soft-404-three-weeks)
- Blog (why we raise this measure): [https://migurei.ai/en/blog/llms-txt-pseudo-response-rate](https://migurei.ai/en/blog/llms-txt-pseudo-response-rate)
- [日本語](https://pw.migurei.ai/ja/research/llms-txt-pseudo-response-rate)

This page is written by migurei / Parallel World about our own weekly scan. The free check is our own service.

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