Robots Validator - Check Robots.txt Online

Check the website's robots.txt file

Robots.txt Validator - Free Online Robots.txt File Checking Tool

Free tool to check and validate your website's robots.txt file online. Detect syntax errors, missing User-agent directive, invalid Sitemap URL, Crawl-delay in wrong format. Automatically fetch robots.txt from URL or paste content for offline testing. Display detailed results with success/warning/error for each line.

Outstanding features

Automatically fetch robots.txt from website URL
Validate syntax and all directives
Check User-agent directive (required)
Validate Disallow and Allow directives
Invalid Sitemap URL detection
Warning Crawl-delay don't in correct format
Detect non-standard directives
Paste the content to check offline
Display line numbers for errors
Color-coded results: success/warning/error
No login required, completely free

What is Robots.txt and why does it need validation?

Robots.txt is a text file placed at the root that of the website (example.com/robots.txt) to instruct search engine bots (Googlebot, Bingbot...) which pages to crawl and which pages don't to crawl. Incorrect syntax of a robots.txt file can cause serious consequences: Google don't able to crawl the website (if Disallow: / false), Google is crawling pages don't supposed to be crawled (admin, private pages), Sitemap don't found. The Robots.txt Validator tool helps you check the syntax and logic that of the robots.txt file BEFORE deploying, ensuring there are no errors affecting SEO and crawling.

Benefits when used

  • Avoid crawling issues - make sure Google crawls the right page
  • Detect syntax errors - syntax errors can break the entire file
  • Validate Sitemap - ensures Google finds the sitemap
  • Pre-deploy check - test before uploading to the server
  • Debug indexing issues - find out why the page is not indexed
  • Learn robots.txt - understand how to write robots.txt correctly

How to use Robots.txt Validator

  1. 1Method 1: Enter the website URL (for example: https://example.com) and press Enter
  2. 2The tool will automatically fetch /robots.txt from that domain
  3. 3Method 2: Paste the robots.txt content directly into the textarea
  4. 4The tool will validate as soon as you paste
  5. 5View results: Success (green), Warning (yellow), Error (red)
  6. 6Fix detected issues
  7. 7Test again after fixing

Frequently Asked Questions (FAQ)

What is Robots.txt?

Robots.txt is a text file placed at the root of the website (example.com/robots.txt) according to Robots Exclusion Protocol. It instructs search engine bots (crawlers) which URLs to crawl and which URLs not to crawl. This is the 'gentleman agreement' - bots can ignore it but major search engines obey it.

Does Disallow block indexing?

NOT at all. Disallow only prevents bots from CRAWLing the page (not reading the content), but if there are links from another page pointing to it, Google can still INDEX that URL (shown in search results with 'No information available'). To completely block indexing, use the noindex meta tag or X-Robots-Tag header.

Is Sitemap required in robots.txt?

Not required but RECOMMENDED. Adding 'Sitemap: https://example.com/sitemap.xml' helps search engines find the sitemap faster, especially for new websites. However, you SHOULD also submit your sitemap via Google Search Console just to be sure.

Does crawl-delay work with Google?

ARE NOT. Google does NOT follow Crawl-delay in robots.txt. To adjust Google's crawl rate, use Google Search Console > Settings > Crawl rate. Crawl-delay only works with some other bots such as Bing and Yandex. The value is the number of seconds between requests.

What does User-agent: * mean?

User-agent: * applies rules to ALL bots. You can specify rules for each bot: User-agent: Googlebot (Google only), User-agent: Bingbot (Bing only). Specific rules will override general rules. If there is no User-agent, the robots.txt file is invalid.

How are Allow and Disallow different?

Disallow: /path/ prevents bots from crawling URLs starting with /path/. Allow: /path/exception/ allows crawling exceptions in disallowed paths. Allow is useful when you want to block folders but allow some files. For example: Disallow: /admin/ + Allow: /admin/public/ = block /admin/ but allow /admin/public/.

How do wildcards in robots.txt work?

* match any sequence of characters. $ match end of URL. For example: Disallow: /*.pdf$ blocks all URLs ending in .pdf. Disallow: /*/private/ block /a/private/, /b/private/... Note: not all bots support wildcards, but Google and Bing do.

Is Robots.txt case-sensitive?

Directives (User-agent, Disallow, Allow) are case-insensitive. But URL paths are case-sensitive on most servers. /Admin/ and /admin/ are different. Best practice: match exact cases of URLs on the website.

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