Ahrefs gets blocked because websites see it as a bot that crawls their pages without permission
Ahrefs runs a web crawler — a bot that visits millions of websites to collect data about links, keywords, and site structure. Website owners can block this crawler the same way they block any other bot, by adding Ahrefs to their robots.txt file or by using server rules that reject requests from Ahrefs' IP addresses. When a site blocks Ahrefs, the crawler cannot reach that site's pages, so Ahrefs cannot include that site's data in its reports.
This is not a punishment or a technical error. It is a deliberate choice by the website owner. They decide whether to let Ahrefs in, just as they decide whether to let Google in. Some sites block Ahrefs because they do not want competitors analyzing their backlinks or keyword strategy. Others block it for privacy reasons or because they simply do not want any third-party crawlers on their servers.
The result is that Ahrefs' database has gaps. If a major competitor or a high-authority site blocks Ahrefs, you will not see their full link profile or their exact keyword rankings in Ahrefs reports. This affects the accuracy of the data you get when you research competitors or analyze your own site's performance.
Key Takeaways
- Websites block Ahrefs by adding it to their robots.txt file or by using server-level IP blocking, which prevents the Ahrefs crawler from accessing their pages.
- Blocked sites do not appear in Ahrefs' backlink database, so you cannot see the full link profile of competitors who use blocking.
- Large sites and direct competitors are more likely to block Ahrefs than small or new sites, which creates blind spots in competitive research.
- Ahrefs still shows you most of the web — the blocked sites represent a small percentage of total links and data — but you should know which major sites are blocked when interpreting reports.
- You can check whether a specific site blocks Ahrefs by looking at its robots.txt file or by seeing whether Ahrefs has recent crawl data from that domain.
How websites block Ahrefs
The most common method is the robots.txt file. Every website can create a robots.txt file in its root directory — the file sits at something like example.com/robots.txt — and it tells crawlers which parts of the site they can and cannot visit. A site owner can add a rule that says "Disallow: /" for the Ahrefs user-agent, which blocks Ahrefs completely while allowing Google and other crawlers through.
The second method is server-level blocking. A website administrator can configure their server to reject all requests from Ahrefs' IP address ranges before the request even reaches the site's pages. This is more aggressive than robots.txt because it stops Ahrefs at the door, whereas robots.txt is more of a polite instruction that a crawler can technically ignore.
A third method, less common but still used, is the .htaccess file or similar server configuration that blocks specific user-agents. This works similarly to robots.txt but operates at the server level and is harder for a crawler to work around.
Why major sites and competitors block Ahrefs
Large websites and direct competitors are the most likely to block Ahrefs. They do this because Ahrefs data is valuable — if you can see exactly which sites link to your competitor, you know where to pitch your own content or where to build relationships. By blocking Ahrefs, a competitor makes it harder for you to reverse-engineer their link strategy.
Some large sites block all third-party crawlers except Google because they want to control who accesses their data and how it is used. They may have privacy concerns, or they may simply not want to share their backlink profile with the public. Financial sites, news organizations, and SaaS companies are particularly likely to block Ahrefs.
Small and new sites rarely block Ahrefs because they do not have the technical knowledge to set it up, and they often want the visibility that comes from appearing in Ahrefs' public database. A startup wants to be found and analyzed; an established competitor wants to stay hidden.
What gaps in Ahrefs data actually mean for your research
Ahrefs still covers the vast majority of the web. The sites that block Ahrefs represent a small percentage of total links and domains, so most of your competitive research will still be accurate. You will see the majority of backlinks pointing to your competitors, the majority of keywords they rank for, and a realistic picture of their SEO strategy.
The blind spots matter most when you are researching a direct competitor who blocks Ahrefs, or when you are trying to understand links from a major authority site that blocks crawlers. If Forbes or TechCrunch blocks Ahrefs and your competitor has a link from one of those sites, you will not see it in Ahrefs. This means your competitive analysis is incomplete for that specific competitor.
In practice, this usually means you should cross-check important findings with other tools. If Ahrefs shows that a competitor has 500 backlinks but you suspect they have more, you can use Google Search Console (if you have access to their account, which you usually do not) or a different tool like SEMrush or Moz to see whether the picture changes. Often it does not — Ahrefs is still the most comprehensive — but it is worth knowing the limitation exists.
How to check whether a site blocks Ahrefs
The simplest way is to look at the site's robots.txt file directly. Go to the domain you want to check, add /robots.txt to the end, and look for any rule that mentions "ahrefs" or "AhrefsBot". For example, visit example.com/robots.txt and search the page for "ahrefs". If you find a rule like "User-agent: AhrefsBot" followed by "Disallow: /", that site is blocking Ahrefs.
You can also check inside Ahrefs itself. If you run a Site Audit on a domain, Ahrefs will tell you whether it was able to crawl the site. If Ahrefs shows zero pages crawled or very few pages despite the site being large and active, the site is likely blocking Ahrefs. Similarly, if you look up a domain in Ahrefs' Site Explorer and see no backlink data or very little data, that domain may be blocking the crawler.
Keep in mind that a site might block Ahrefs but still appear in Ahrefs' database if other sites link to it. Ahrefs learns about blocked sites through backlinks from sites it can crawl. So a blocked site might show up in reports as "this site links to you" even though Ahrefs cannot visit that site directly.
Whether you should block Ahrefs on your own site
Most websites should not block Ahrefs. Blocking Ahrefs means your site will not appear in competitors' research, which sounds good until you realize it also means you lose visibility in a major SEO tool. If you are trying to build authority and attract links, you want to be visible in Ahrefs so that people researching your industry can find you.
The only reason to block Ahrefs is if you have a specific privacy concern or if you are in a highly competitive industry where you believe the cost of visibility outweighs the benefit of hiding your link profile. Even then, blocking Ahrefs alone does not hide you — you would need to block all third-party crawlers, and that would also prevent Google from indexing your site, which defeats the purpose of SEO.
If you do decide to block Ahrefs, add this line to your robots.txt file: "User-agent: AhrefsBot" on one line, then "Disallow: /" on the next line. This tells Ahrefs to stop crawling your site. The change takes effect within a few days as Ahrefs respects the robots.txt standard.
Other tools that face similar blocking
Ahrefs is not alone. SEMrush, Moz, and other SEO tools run their own crawlers, and websites block them using the same methods. Some sites block all third-party crawlers indiscriminately. Others block only the most popular ones — Ahrefs and SEMrush — while allowing smaller tools through.
Google's crawler is almost never blocked because websites need Google to index them for search visibility. Bing's crawler is also rarely blocked. But any tool that does not directly affect your search ranking is fair game for blocking, and many site owners do block them.
This means that no single SEO tool has a complete picture of the web. Every tool has blind spots. Ahrefs is the most comprehensive, but it is not perfect. When you are making important decisions based on SEO data, it is worth knowing which sites are blocked and whether that affects your analysis.
Frequently Asked Questions
Does blocking Ahrefs hurt my Google rankings?
No. Blocking Ahrefs only prevents Ahrefs' crawler from visiting your site. It does not affect Google's crawler or your search visibility. Google will still index your site normally, and your rankings will not change. Blocking Ahrefs is purely about controlling who can see your backlink data.
If a competitor blocks Ahrefs, can I still see their backlinks?
You can see some of their backlinks — the ones from sites that Ahrefs can crawl. But you cannot see backlinks from other sites that also block Ahrefs, and you cannot see the full structure of their site. You will get an incomplete picture, but usually still enough to understand their general link strategy.
Why does Ahrefs respect robots.txt if it is just a suggestion?
Ahrefs respects robots.txt because it is the industry standard and because violating it would damage Ahrefs' reputation and relationships with website owners. Crawlers could technically ignore robots.txt, but responsible crawlers follow it. Google does the same.
Can I block Ahrefs but allow Google?
Yes. You can add a specific rule in robots.txt that blocks only AhrefsBot while allowing Googlebot and other crawlers through. This is common among large sites that want to hide their data from competitors but still need Google to index them.
How much of the web does Ahrefs actually cover?
Ahrefs covers the vast majority of the publicly crawlable web — estimates vary, but it is typically in the range of 90 percent or higher of pages that are not blocked. The blocked sites represent a small percentage, though some of those blocked sites are high-authority domains that matter for competitive research.