Free SEO Tool

SEO Crawler Checker

See how search engines and AI bots view your website. Select a crawler, enter a URL, and get a visual preview with SEO metadata analysis.

Search Engine Crawlers

AI Crawlers

How Search Engines and AI Bots See Your Website

When a search engine like Google or an AI assistant like ChatGPT visits your website, it doesn't see the same thing you do in your browser. Crawlers use specific User-Agent strings to identify themselves, and many websites serve different content based on who is visiting. Additionally, not all crawlers can execute JavaScript — which means your beautifully rendered React or Vue application might appear as a blank page to some bots.

The SEO Crawler Checker lets you see exactly what these bots receive when they visit your pages. Choose from 14+ popular search engine and AI crawlers, enter any URL, and get an instant visual preview along with critical SEO metadata.

Why This Matters

  • JavaScript rendering gaps — SPAs and client-side rendered pages may appear empty to crawlers that don't execute JavaScript, costing you search visibility
  • Cloaking detection — accidentally serving different content to bots vs. users can trigger Google penalties
  • AI training visibility — understand what content AI models like GPT and Claude are trained on from your site
  • Meta tag verification — confirm that your title, description, canonical, and Open Graph tags are correctly set and visible to crawlers
  • robots.txt compliance — verify which crawlers are actually able to access your pages

Rendered vs. Raw HTML

Rendered mode simulates modern crawlers like Googlebot that use a headless Chromium browser to execute JavaScript before reading the page. You get a full screenshot and the rendered DOM — exactly what Google indexes.

Raw HTML mode shows the initial server response without any JavaScript execution. This is what most AI crawlers and simpler bots see. If your site relies on client-side rendering, this mode will reveal whether your content is accessible without JavaScript.

For JavaScript-heavy websites, pre-rendering bridges this gap by serving fully rendered static HTML to all crawlers — ensuring every bot sees your complete content, regardless of its JavaScript capabilities.

Frequently Asked Questions

What is a web crawler and why does it matter for SEO?
A web crawler (also called a bot or spider) is an automated program that visits websites to read and index their content. Search engines like Google use crawlers to discover pages and determine how they rank in search results. AI services like ChatGPT and Claude use crawlers to gather information for their responses. Understanding how these bots see your pages is essential for SEO because they may see different content than regular users — especially on JavaScript-heavy websites.
How does the SEO Crawler Checker work?
The tool fetches your page using the exact User-Agent string of the selected crawler. In "Rendered" mode, it uses a headless browser to execute JavaScript, take a screenshot, and capture the fully rendered DOM — just like Googlebot would. In "Raw HTML" mode, it makes a simple HTTP request and returns the raw server response, showing what non-rendering bots receive.
What is the difference between "Rendered" and "Raw HTML" modes?
Rendered mode uses a headless browser (like Puppeteer/Chromium) to fully load and execute JavaScript on the page, then captures a screenshot and the rendered DOM. This simulates how modern crawlers like Googlebot see your site. Raw HTML mode makes a basic HTTP request and returns the HTML exactly as the server sends it — without executing any JavaScript. This shows what simpler bots and older crawlers receive.
Why might a crawler see different content than I do?
Several factors can cause differences: JavaScript rendering (some bots don't execute JS), server-side user agent detection (serving different content to bots), robots.txt rules blocking specific crawlers, geo-based content delivery, authentication walls, and cloaking. This tool helps you detect these discrepancies.
Which crawlers are supported?
The tool supports major search engine crawlers (Googlebot, Googlebot Mobile, Bingbot, YandexBot, Baiduspider, Yahoo Slurp, Applebot) and leading AI crawlers (GPTBot, ChatGPT Browse, ClaudeBot, PerplexityBot, Meta AI, Google Gemini, Cohere AI). Each uses its official User-Agent string.
What SEO metadata does the tool analyze?
The tool extracts and displays key SEO elements: page title, meta description, canonical URL, robots meta tag, Open Graph title, Open Graph description, and Open Graph image. These are the most important tags that search engines and social media platforms use to understand and display your content.
Is this tool free to use?
Yes, the SEO Crawler Checker is completely free with no registration required. You can test as many pages and crawlers as you need.
How often should I check how crawlers see my site?
You should check after any major site update, redesign, or deployment of new JavaScript features. It's also good practice to run checks after changing your robots.txt, updating meta tags, or switching between client-side and server-side rendering. For sites that rely heavily on JavaScript rendering, monthly checks are recommended.