Published on 2025-08-07T06:18:08Z

AhrefsSiteAudit

AhrefsSiteAudit is a specialized diagnostic web crawler from the SEO company Ahrefs. Unlike their main crawler, this bot is initiated directly by Ahrefs users to perform comprehensive technical SEO audits on specific websites. It analyzes sites for issues like broken links, slow performance, and duplicate content to provide actionable recommendations for improvement. Its presence indicates that someone is actively analyzing your site's health using the Ahrefs platform.

What is AhrefsSiteAudit?

AhrefsSiteAudit is a specialized web crawler operated by Ahrefs, a leading provider of SEO and marketing tools. This bot is the engine behind Ahrefs' Site Audit tool, designed to analyze websites for technical and on-page SEO issues. It identifies itself with distinct user-agent strings for desktop and mobile, such as Mozilla/5.0 (compatible; AhrefsSiteAudit/6.1; +http://ahrefs.com/robot/site-audit). Unlike general-purpose crawlers, AhrefsSiteAudit is more advanced, capable of rendering JavaScript and evaluating page performance to simulate real user and search engine interactions. It is recognized as a legitimate and well-behaved bot, verified by Cloudflare.

Why is AhrefsSiteAudit crawling my site?

The AhrefsSiteAudit crawler visits your site only when an Ahrefs user has initiated an audit on your domain. This user could be a member of your own team, an SEO agency you've hired, or even a competitor researching your site's technical setup. The bot looks for a wide range of technical issues, including broken links, duplicate content, slow-loading pages, and improper metadata. The frequency of visits is determined by the audit schedule set by the user, which can be a one-time scan or a recurring weekly or monthly check. While a crawl initiated by you is authorized, one from a third party may be unauthorized, but the bot still adheres to standard web protocols.

What is the purpose of AhrefsSiteAudit?

The primary purpose of AhrefsSiteAudit is to provide the data for Ahrefs' Site Audit tool, which helps website owners identify and resolve technical SEO problems. The crawler meticulously checks for issues such as slow performance, security misconfigurations, crawlability problems, and mobile responsiveness errors. The collected data is then compiled into detailed reports that categorize issues by severity and offer clear recommendations for fixing them. For website owners, this provides immense value by uncovering critical issues that could be harming their search engine rankings and overall user experience.

How do I block AhrefsSiteAudit?

If you wish to prevent anyone from running an Ahrefs Site Audit on your website, you can block the AhrefsSiteAudit crawler. Add the following rule to your site's robots.txt file.

To block the bot, use this directive:

User-agent: AhrefsSiteAudit
Disallow: /

How to verify the authenticity of the user-agent operated by Ahrefs?

Reverse IP lookup technique

To verify user-agent authenticity, you can use host linux command two times with the IP address of the requester.

```
> host IPAddressOfRequest
```
This command returns the reverse lookup hostname (e.g., 4.4.8.8.in-addr.arpa.).

> host ReverseDNSFromTheOutputOfFirstRequest

If the output matches the original IP address and the domain is associated with a trusted operator (e.g., Ahrefs), the user-agent can be considered legitimate.

IP list lookup technique

Some operators provide a public list of IP addresses used by their crawlers. This list can be cross-referenced to verify a user-agent's authenticity. However, both operators and website owners may find it challenging to maintain an up-to-date list, so use this method with caution and in conjunction with other verification techniques.