When Google crawls your website, it’s not always a smooth process. Sometimes, it encounters a problem it can’t fully categorize. Google Search Console labels these events as “Crawl anomalies.”
A crawl anomaly is a catch-all term for an unexpected issue that prevented Google from crawling a page as it expected. These can be minor, temporary glitches or signs of a deeper problem on your site. Performing a Technical SEO Audit helps identify and fix crawl anomalies, ensuring all your important pages get properly indexed.
What Is a Crawl Anomaly in Google Search Console?
A crawl anomaly is a specific type of crawl error reported in Google Search Console. It’s a broad category that indicates something went wrong during Google’s attempt to access a URL, but the problem doesn’t fit into a more specific error category.
How does Google define a crawl anomaly?
Google defines a crawl anomaly as an error where the crawler encountered a problem that prevented it from successfully fetching a URL, but the issue wasn’t a clear server error, a “not found” status, or a robots.txt block. It’s an ambiguous crawl failure.
Where can you find crawl anomalies in the Index Coverage report?
You can find crawl anomalies within the “Pages” section of Google Search Console. Navigate to “Index” and then “Pages.” The report will show a section for “Page with crawl anomaly.” Clicking on this will show you a list of all URLs that have this specific issue.
What makes crawl anomaly different from other crawl errors?
Unlike other crawl errors, a crawl anomaly doesn’t have a specific, clear-cut cause. For example, a “404 not found” error means the page doesn’t exist. A “server error (5xx)” means there was an issue with your server. A crawl anomaly is a less defined issue. It’s often a temporary problem, but it can also be a symptom of a larger, persistent technical issue.
Why Do Crawl Anomalies Occur on Websites?
Crawl anomalies can stem from various sources. Most are related to issues that prevent Googlebot from getting a clean connection or response from your server.
What role do HTTP status codes (4xx, 5xx) play in crawl anomalies?
Crawl anomalies are often tied to strange or inconsistent HTTP status codes. While a “404 not found” is a clear signal, sometimes a page might return an unusual 4xx code (like 403 Forbidden) that Google doesn’t fully understand, or a temporary 5xx error that resolves before Google can properly log it.
Can robots.txt blocking cause crawl anomalies?
While a direct robots.txt block is a separate issue in Search Console, a misconfigured or temporarily unavailable robots.txt file can sometimes lead to a crawl anomaly. If Googlebot can’t access the robots.txt file to determine what to crawl, it may report an anomaly.
How do login restrictions or access permissions trigger anomalies?
Pages that require a login or have strict access permissions can cause crawl anomalies. If Googlebot tries to crawl a page that is behind a login wall, it will be denied access. Since this isn’t a simple 404 or a server error, it can be flagged as a crawl anomaly.
Do server errors and timeouts show up as crawl anomalies?
Yes. While a consistent 5xx server error has its own category, a temporary server timeout or a brief, intermittent 5xx error can be reported as a crawl anomaly. If the server is slow to respond or times out during the crawl, Googlebot may not be able to get a proper response, leading to this error.
Common technical misconfigurations that confuse Googlebot
Issues like incorrect server settings, firewalls that block specific user agents, or content management system (CMS) errors can all confuse Googlebot. These technical misconfigurations don’t always result in a standard error code, leading to a crawl anomaly.
How Do Crawl Anomalies Impact SEO Performance?
A crawl anomaly means a page was not successfully crawled. This has a direct impact on its ability to be indexed and ranked.
Do crawl anomalies stop pages from being indexed?
Yes. If a page has a crawl anomaly, Google has not been able to access its content. A page that can’t be crawled can’t be indexed. This means the page will not appear in search results.
Can too many crawl anomalies hurt crawl budget?
Yes. Crawl budget is the number of pages Google is willing to crawl on your site. If Googlebot repeatedly encounters crawl anomalies, it may spend less time crawling your site. This can lead to Google not finding and indexing new or updated content.
When should you worry about large numbers of crawl anomalies?
A few anomalies on a large site are often not a concern. They can be temporary. However, a sudden spike or a consistently high number of crawl anomalies indicates a significant underlying problem with your site’s health. This requires immediate investigation.
How Can You Diagnose Crawl Anomalies?
Diagnosing crawl anomalies involves looking beyond Google Search Console to understand the root cause.
How do you use the URL Inspection tool for crawl anomalies?
The URL Inspection tool is your first step. Enter the URL with the anomaly into the tool. This will show you exactly how Google sees the page. The tool might reveal a temporary server error, a redirect chain, or a problem with rendering the page.
What do server log files reveal about failed crawls?
Server logs are a powerful diagnostic tool. They provide a detailed record of every request made to your server, including those from Googlebot. By analyzing logs for the URLs with anomalies, you can see if the server returned a specific error code or if the connection was terminated. Since these files can be very large and difficult to read, a Summarizer Tool can help you quickly extract the key issues.
Which SEO tools help uncover crawl anomalies? (Screaming Frog, Sitebulb, etc.)
While traditional crawlers like Screaming Frog are great, a tool like the ClickRank Audit goes further. It connects directly to Google Search Console to show you real issues based on real user data. Instead of just crawling your site, it prioritizes and highlights specific issues like crawl anomalies, giving you actionable fixes.
Step-by-step crawl anomaly audit checklist
- Check Google Search Console: Identify all URLs with a crawl anomaly.
- Use URL Inspection Tool: Test a sample of the affected URLs.
- Analyze Server Logs: Look for the specific crawl attempts from Googlebot for those URLs.
- Run a Site Crawl: Use a tool like Screaming Frog to see if you can replicate the error.
- Identify Patterns: Look for commonalities. Are the URLs on a specific subdomain? Are they all new pages? Do they share a common template?
How Do You Fix Crawl Anomalies Effectively?
Fixing crawl anomalies requires a systematic approach based on the underlying cause.
What are the first steps to resolve crawl anomalies?
Start by using the URL Inspection tool on the affected pages. This will often reveal a simple, fixable issue. If the tool shows “URL is on Google,” the issue might be temporary. If it shows an error, investigate that specific error.
How do you fix issues caused by blocked resources or robots.txt?
Check your robots.txt file and ensure it is not unintentionally blocking important CSS, JavaScript, or other resources. If the issue is with a blocked resource, you may need to adjust your robots.txt file to allow Googlebot to access it.
What server fixes help eliminate crawl anomalies?
If server timeouts or intermittent errors are the cause, your server may be underpowered or misconfigured. Talk to your hosting provider or a server administrator to optimize server performance and uptime. This is especially important during peak traffic times.
How do you handle authentication-restricted pages?
If the pages are meant to be private, then the anomaly is expected. If they should be public, you need to remove the login requirement or use an authentication method that Google can handle. For example, some sites use specific login methods that block Googlebot.
Can redirects and canonicals cause crawl anomalies?
Yes. Incorrectly implemented redirects or canonical tags can confuse Googlebot. For example, a redirect loop or a canonical tag pointing to an incorrect URL can result in a crawl anomaly.
Prioritizing crawl anomaly fixes by SEO impact
Focus your efforts on pages that are important for your business. Start with pages that should be indexed and are generating traffic. Fixing anomalies on these pages should be a priority. Less important pages can be addressed later.
How Do Crawl Anomalies Differ From Other Index Coverage Issues?
It’s easy to confuse a crawl anomaly with other errors in Search Console.
Crawl anomaly vs. Crawled – currently not indexed
“Crawled – currently not indexed” means Google successfully crawled the page but chose not to add it to its index. This is often because the page is thin, has duplicate content, or is not considered important. A crawl anomaly means Google couldn’t crawl the page at all.
Crawl anomaly vs. Blocked by robots.txt
“Blocked by robots.txt” is a specific error. Googlebot was told by your robots.txt file to not crawl a page and respected that command. A crawl anomaly is a failure to crawl for a different, undefined reason.
Crawl anomaly vs. Soft 404 and 404 not found
A “404 not found” is a clear signal that a page doesn’t exist. A “soft 404” is a page that returns a 200 OK status code but looks like a 404 page to Google. A crawl anomaly is a more ambiguous error.
Crawl anomaly vs. Server errors (5xx)
“Server errors (5xx)” indicates a clear issue with the server. A crawl anomaly can be caused by a temporary 5xx error, but it is not a persistent server-side issue.
Can Crawl Anomalies Resolve Themselves?
Sometimes, yes. If the anomaly was caused by a temporary server glitch, it may resolve on its own.
When does Google re-crawl affected URLs automatically?
Google automatically re-crawls URLs. How often it does so depends on the importance of the page and how often it changes. Google will try again to crawl the page.
How long should you wait before taking action?
If you see a small number of anomalies, you can wait a few days to see if they disappear. However, if the number is large or persistent, you should investigate and fix the issue.
Should you request re-indexing in GSC for crawl anomalies?
After you fix the issue, you should use the URL Inspection tool to “Request Indexing.” This tells Google to re-crawl the page sooner.
How Do You Monitor and Prevent Crawl Anomalies Long Term?
Prevention is better than a cure. Proactive monitoring can save you from a bigger problem.
What monitoring tools alert you to crawl anomalies quickly?
Regularly checking Google Search Console is the best way to monitor. For larger sites, tools like Sitebulb can be set up to perform regular crawls and alert you to new issues.
How can better internal linking reduce anomalies?
Strong internal linking helps Google find and crawl your important pages. A well-organized internal link structure can help Googlebot navigate your site and reduce the chances of encountering a crawl anomaly.
How do site architecture and URL hygiene prevent crawl errors?
A clean site architecture and consistent URL structure make it easier for Google to crawl your site. Avoid broken links, redirect chains, and confusing URL patterns.
Best practices checklist for avoiding crawl anomalies
- Monitor GSC regularly: Check the Index Coverage report weekly.
- Optimize server performance: Ensure your server is stable and responsive.
- Maintain clean URLs: Avoid unnecessary parameters and confusing URL structures.
- Use correct redirects: Fix any redirect chains or loops.
- Review robots.txt: Make sure it is not blocking important files.
Is crawl anomaly harmful for SEO rankings?
A crawl anomaly prevents a page from being indexed. If a page can't be indexed, it can't rank. So yes, they are harmful to SEO rankings.
Does fixing crawl anomalies improve indexing immediately?
Fixing the problem and requesting re-indexing can speed up the process. However, the page won't appear in search results instantly.
Why do some URLs show crawl anomalies even if they load fine in a browser?
A browser and Googlebot are different. Your browser might use a cache, or your server might be configured to serve content differently to Googlebot. The URL Inspection tool shows you what Googlebot sees.
Do crawl anomalies affect small sites differently than large sites?
For a small site, even a few anomalies can be a major problem. For a large site, a small percentage of anomalies may be acceptable, but a sudden spike is a serious issue.
