llms.txt Last-Modified Checker

Inspect the HTTP freshness metadata published with a website’s /llms.txt file.

llms.txt Last-Modified Checker

Review update dates and cache validators

Free

Check llms.txt freshness metadata

Enter a domain to inspect its Last-Modified response header.

Enter a website to inspect its llms.txt modification metadata.

What Is the llms.txt Last-Modified Checker?

This tool checks whether a server publishes a Last-Modified HTTP header with its llms.txt response. When present, the header indicates when the server believes the resource last changed.

Why Last-Modified Metadata Helps

Freshness metadata allows clients and caches to avoid downloading an unchanged file repeatedly. An ETag can provide a second cache validator even when Last-Modified is unavailable.

Does a Missing Header Mean the File Is Stale?

No. The header is optional and its absence does not reveal the true age of the content. It only means the server did not provide this particular freshness signal.

Free WordPress plugin

Publish your llms.txt automatically

Generate and maintain a clean /llms.txt endpoint from your WordPress posts, pages, categories and public custom post types.

Download free plugin View plugin features

Related Components

llms.txt Generator & Builder Create an llms.txt file manually, from a sitemap or from a list of URLs. llms.txt Validator Check syntax, Markdown and structure. llms.txt Formatter Clean, beautify and reorder sections. llms.txt Converter Convert between CSV, JSON and HTML. llms.txt Link Checker Find broken and duplicate URLs. llms.txt Analyzer & Previewer Preview, URLs, sections and word count.

Questions you might have

Is Last-Modified required for llms.txt?
No. It is optional HTTP metadata, but it can improve caching and freshness checks.
What is an ETag?
An ETag is a server-provided identifier for a specific version of a resource and can be used for conditional requests.
Can the Last-Modified date be inaccurate?
Yes. It depends on server configuration, deployment behavior and how the file is generated.
Does a recent date guarantee fresh content?
No. It only reports the server timestamp and does not evaluate the accuracy or quality of the file.
Why is the header missing?
Dynamic responses, CDN settings, server configuration or privacy choices may omit Last-Modified metadata.
llms.txt File Size Checker Measure the exact byte size, characters and lines. llms.txt Generator & Builder Create an llms.txt file manually, from a sitemap or from a list of URLs.