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Technical SEO

What Is Robots.txt?

Robots.txt is a text file at the root of a website (example.com/robots.txt) that tells search engine and AI crawlers which pages and directories they are allowed or disallowed from accessing. It uses User-Agent directives to control access per crawler.

Why Robots.txt matters for SEO

In 2026, robots.txt controls access for both search engines (Googlebot, Bingbot) and AI crawlers (GPTBot, OAI-SearchBot, ClaudeBot, Claude-SearchBot, PerplexityBot). Blocking AI search crawlers means your content won't appear in ChatGPT, Claude, or Perplexity results. Many sites accidentally block AI crawlers, losing all AI search visibility.

Pro tip on Robots.txt

Allow search crawlers (Googlebot, Bingbot) and AI search crawlers (OAI-SearchBot, Claude-SearchBot, PerplexityBot). You can optionally block AI training crawlers (GPTBot, ClaudeBot, Google-Extended) without affecting search visibility. Include a Sitemap directive pointing to your XML sitemap.

Related terms

Crawl Budgetrobots.txt helps conserve crawl budget by blocking low-value pagesXML SitemapThe Sitemap directive in robots.txt tells crawlers where to find your sitemapAI CrawlerAI crawlers like GPTBot and ClaudeBot respect robots.txt directives

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