AI User-Agent Crawlers: The Complete 2025 List
▼ Summary
– Controlling AI crawler access is essential for SEO visibility in AI discovery engines, but unmonitored crawlers can overload servers.
– Identifying AI crawlers is challenging due to outdated official documentation and some agents, like you.com and ChatGPT’s Atlas, not using identifiable user-agent strings.
– Server logs can be analyzed using hosting UIs, FTP, or tools like Google Sheets and Screaming Frog to monitor crawling activity.
– Fake crawlers can spoof user-agent strings, so verification against official IP lists is the most reliable method to block illegitimate bots.
– Regularly checking and updating your AI crawler management, via server logs and tools like robots.txt or firewalls, is necessary to maintain desired AI visibility.
For any website owner or SEO professional, managing how artificial intelligence systems access your content is now a fundamental task. AI visibility plays a crucial role for SEOs, and this starts with controlling AI crawlers. If these automated agents cannot reach your pages, your site remains invisible to the growing number of AI-powered discovery tools and search engines. Conversely, allowing unrestricted access can lead to server strain from excessive requests, potentially causing performance issues and unexpected costs. The key to this control lies in accurately identifying these crawlers through their user-agent strings, a process often hampered by incomplete or outdated official information.
To address this challenge, we have compiled a verified list of active AI crawlers, directly sourced from actual server logs. Each entry has been cross-referenced with official IP address lists where available to ensure reliability. This resource will be regularly updated to reflect the emergence of new crawlers and changes to existing ones.
The Complete Verified AI Crawler List (December 2025)
The user-agent strings provided have all been confirmed through analysis of server access logs.
Popular AI Agent Crawlers With Unidentifiable User Agents
Our monitoring has identified several prominent AI services that do not clearly identify themselves in their user-agent strings. These include:
Without a distinctive user-agent, tracking these crawlers becomes difficult. The primary method involves identifying their specific IP addresses. One practical technique is to create a dedicated trap page on your server and use the AI’s own interface to prompt it to visit that unique URL. By then reviewing the server logs for that specific page request, you can isolate and record the corresponding IP address.
The Challenge of Agentic AI Browsers
A further complication arises with agentic AI browsers like Comet or ChatGPT’s Atlas. These tools do not differentiate themselves in their user-agent strings, making their visits indistinguishable from those of regular human users in server logs. This presents a significant hurdle for SEO reporting, as it becomes nearly impossible to track and quantify visits from these increasingly common AI-driven browsing agents.
How To Check What’s Crawling Your Server
Understanding your own traffic begins with accessing your server logs. Many hosting providers offer a user-friendly interface to view these logs directly. If your host does not provide this, you can typically obtain the log files via FTP or by requesting them from your server support team. On Linux-based servers, these are commonly found at `/var/log/apache2/access.log`.
Once you have the log file, you can analyze it using several tools. Options include importing CSV-formatted logs into Google Sheets, using dedicated software like Screaming Frog’s Log File Analyzer, or, for smaller files under 100 MB, leveraging an AI assistant like Gemini to help parse and interpret the data.
How To Verify Legitimate Vs. Fake Bots
A critical security consideration is the prevalence of fake crawlers. Malicious actors can spoof legitimate user agents to bypass basic restrictions and aggressively scrape content. For instance, anyone can use a command-line tool to send a request that appears to come from a known bot like ClaudeBot.
The most reliable method for verification is to check the requesting IP address against the officially published IP ranges for that crawler. If the IP matches the official list, the request is likely legitimate. If the user-agent claims to be a known AI bot but the IP address does not match, it is likely an impersonation attempt.
Implementing this verification can conserve server bandwidth and protect your content from unauthorized harvesting. Various firewall solutions can automate this process. You can create an allowlist of verified IPs from official sources, permitting only traffic from those addresses when paired with the corresponding user-agent. All other requests impersonating AI crawlers are then blocked.
For WordPress sites, plugins like the free version of Wordfence can facilitate this. You can add the official IP ranges to an allowlist and create custom rules to block impersonators. It is important to note that while this method is highly effective, sophisticated attacks involving IP address spoofing can sometimes bypass these checks.
Staying In Control For Reliable AI Visibility
AI crawlers are a permanent fixture of the modern web ecosystem. The bots listed represent the major platforms currently indexing online content, though this landscape will undoubtedly expand. Regularly reviewing your server logs is essential to understand what is accessing your site. This practice ensures you do not accidentally block crawlers if AI search visibility is important for your goals. If you wish to prevent AI from accessing your content, you can explicitly block them using the `robots.txt` file and the appropriate user-agent name.
We are committed to maintaining this list as a current resource. New crawlers will be added, and existing entries will be updated as information changes. We recommend bookmarking this page or revisiting periodically to keep your access controls aligned with the evolving digital environment.
(Source: Search Engine Journal)
