Your Robots.txt & Sitemap.xml Validator
Free robots.txt and sitemap.xml validator. Paste or fetch either file and get instant errors and warnings — accidental Disallow: /, missing Sitemap line.
- Free to use
- No signup
- Nothing to install
- Works in any modern browser
<code>User-agent: *\nDisallow: /</code> with no Sitemap line → flagged as "blocks ALL search engines" and "no Sitemap directive found".Open the Robots.txt & Sitemap.xml Validator
Illustration. Open the tool for the real thing.
What is the Robots.txt & Sitemap.xml Validator?
A single stray character in robots.txt — a slash where there shouldn't be one — can hide an entire website from Google. This tool checks your robots.txt line by line: it confirms every directive (User-agent, Disallow, Allow, Sitemap, Crawl-delay) uses valid syntax, flags unknown or misplaced directives, and specifically calls out the most damaging mistake of all — a <code>Disallow: /</code> under <code>User-agent: *</code> that accidentally blocks every search engine from the entire site.
The sitemap side reads a pasted or fetched sitemap.xml (or a sitemap index) and checks its real XML structure: a valid <code><urlset></code> or <code><sitemapindex></code> root, the correct namespace, that every <code><loc></code> is present and an absolute URL, that <code><lastmod></code> dates parse correctly, that <code><priority></code> stays within 0.0–1.0, and that the file does not exceed the 50,000-URL limit. You can paste content directly, or try fetching a live URL — robots.txt is usually served with open access since it is meant for crawlers, but sitemap.xml fetches can fail due to the browser's CORS security policy, so a manual paste box is always available as a reliable fallback.
3 steps to your result
Open the tool and follow along. Nothing to install.
What you get
Every directive validated, with line numbers.
Flags Disallow: / and other site-wide blocking mistakes.
Uses the browser's own XML parser, not guesswork.
Tries a live URL first, with a reliable manual fallback.
AZRS tools are free to open and use.
It opens in your browser, so there is nothing to download.
Used for
Pick one to see how it fits.
SEO professionals and site owners
Catch a crawl-blocking mistake before it costs rankings.
Try it freeAgencies auditing client sites
Quickly spot the most common on-page technical SEO errors.
Try it freeHow it compares
A plain look at this tool next to the usual alternative.
| This seo tool | Desktop software | |
|---|---|---|
| Install | Nothing to install | Usually an app or program to install |
| Account | No signup | Depends on the product |
| Cost | Free to use | Free or paid, depends on the product |
Questions people ask
Why did fetching my sitemap fail?
Most sites do not send the CORS header that allows browser JavaScript on another domain to read their files. Open the sitemap URL in a new tab, copy its source, and paste it into the box instead.
What does Disallow: / actually do?
It tells the named crawler not to fetch anything on the site. Under User-agent: * it blocks every search engine from the whole site — almost always a mistake.
Do I need a robots.txt at all?
Not strictly, but adding one that at least declares your Sitemap: line helps crawlers find your content faster.
What is the difference between a sitemap and a sitemap index?
A sitemap lists page URLs directly; a sitemap index lists other sitemap files, used when a site has more than 50,000 URLs.
Is my data sent anywhere besides the resolver/site I ask it to fetch?
No. Parsing and validation both run in your browser; a fetch only goes to the exact URL you provide.
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Try the Robots.txt & Sitemap.xml Validator now
Check robots.txt syntax and sitemap.xml structure for errors that block Google. Free to use.
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