AI Search Engine List 2025

AI search engines are reshaping how users find information online. But before they can cite your website, they need to crawl it. Each AI engine has its own crawler with a unique user-agent string.

This guide lists every major AI search engine, its crawler, and what you need to do to make sure your site is accessible to them.

Complete AI Crawler List

1. GPTBot (OpenAI / ChatGPT)

GPTBot is OpenAI's web crawler. It fetches web pages to provide real-time information in ChatGPT responses. With over 200 million weekly active users, being crawlable by GPTBot is critical for AI visibility.

How to allow:

User-agent: GPTBot
Allow: /

Verify with our robots.txt AI checker

2. ClaudeBot (Anthropic / Claude)

ClaudeBot crawls the web for Anthropic's Claude AI assistant. Claude is known for its strong reasoning and coding abilities, and is used by millions of developers and knowledge workers.

How to allow:

User-agent: ClaudeBot
Allow: /

3. PerplexityBot (Perplexity AI)

Perplexity is an AI-first search engine that handles 100M+ queries per day. It crawls the web in real-time to provide cited answers with source links. Unlike ChatGPT, Perplexity always shows its sources — making it especially valuable for driving referral traffic.

How to allow:

User-agent: PerplexityBot
Allow: /

4. Google-Extended (Google AI)

Google-Extended is Google's crawler specifically for AI training and AI-powered features like Google AI Overviews (formerly SGE) and Gemini. It's separate from the regular Googlebot.

How to allow:

User-agent: Google-Extended
Allow: /

⚠️ Many sites accidentally block Google-Extended because it's a newer user-agent not in legacy robots.txt files.

5. CCBot (Common Crawl)

Common Crawl is an open-source web archive that many AI companies use to train their models. If your site is in Common Crawl's dataset, there's a higher chance AI models already "know" about you. Allowing CCBot improves your chances of being referenced in AI-generated content.

How to allow:

User-agent: CCBot
Allow: /

6. Bytespider (ByteDance / Doubao)

Bytespider is ByteDance's crawler, powering AI features in Doubao (豆包), Toutiao (今日头条), and other ByteDance products. With the Chinese AI market growing rapidly, allowing Bytespider ensures visibility in one of the world's largest AI ecosystems.

How to allow:

User-agent: Bytespider
Allow: /

Complete robots.txt for AI Crawlers

Here's a ready-to-use robots.txt that allows all major AI crawlers:

User-agent: *
Allow: /

# AI Crawlers — explicitly allowed
User-agent: GPTBot
Allow: /

User-agent: ClaudeBot
Allow: /

User-agent: PerplexityBot
Allow: /

User-agent: Google-Extended
Allow: /

User-agent: CCBot
Allow: /

User-agent: Bytespider
Allow: /

Sitemap: https://yourdomain.com/sitemap.xml

💡 Check your robots.txt now — see which AI crawlers are allowed or blocked.

AI Search Market Overview (2025)

Should You Allow All AI Crawlers?

For most websites, the answer is yes. Allowing AI crawlers increases your chances of being cited in AI answers, which drives brand awareness and traffic.

You might want to restrict AI crawlers if:

• • Your site has paywalled content (allow crawlers to preview pages, block full content)
• • You're concerned about AI training on your content (but blocking crawlers also means losing AI search visibility)
• • Your server can't handle extra crawl traffic (set crawl-delay instead of blocking)

The tradeoff is simple: block AI crawlers = invisible in AI search. For most businesses, the visibility gain far outweighs the risks.