When search engines like Google crawl your site, they need to access every page smoothly to index your content properly. But what happens when they hit a roadblock? 

Crawl errors can prevent your site from being fully indexed, hurting your visibility and rankings. In fact, studies show that over 20% of pages on the average website have crawl issues, which can lead to lower organic traffic and missed business opportunities. 

In this guide, we’ll break down what crawl errors are, the different types you might encounter, and how to fix them to keep your site search-friendly in 2025.

What Are Crawl Errors?

Crawl errors occur when search engine bots, like Googlebot, have trouble accessing your website’s pages. These errors can prevent your site from being fully indexed, affecting your visibility in search results.

Crawl errors are generally divided into two main categories: site errors and URL errors, which we will discuss in the next section.

Understanding these errors is the first step to ensuring your site is fully optimized for search engines.

Types of Crawl Errors

Understanding the types of crawl errors is crucial for diagnosing and fixing issues that may be holding back your website’s search performance.

1. Site Errors

Site errors happen when search engines can’t access any part of your website. These errors affect your entire site, preventing search engines from crawling and indexing your pages. There are three main types of site errors: DNS errors, server errors, and robots.txt errors.

a. Server Errors

Server errors happen when your web server fails to respond to search engine requests. These errors are like knocking on a door, but no one answers. They can severely impact your site’s crawlability.

Example: You receive a 500 Internal Server Error when trying to visit a page.

Common Types:

• 500 Internal Server Error: General server issue.
• 502 Bad Gateway: Invalid response from an upstream server.
• 503 Service Unavailable: Server is temporarily down.

504 Gateway Timeout: Server didn’t respond in time.

b. DNS Errors

DNS errors occur when the Domain Name System (DNS) can’t locate your website’s IP address. Think of it as trying to call someone but dialing the wrong number. When search engines encounter DNS errors, they can’t find your site at all.

Example: You type a website URL and see a “server not found” message.

Common Causes:

• DNS Timeout: The DNS server didn’t respond to the request quickly enough.
• DNS Lookup Error: The DNS server couldn’t find the domain name.

c. Robots.txt Errors

Robots.txt errors occur when there’s a problem with the robots.txt file, which tells search engines which pages to crawl. It’s like giving incorrect directions to a visitor, causing them to miss important areas.

Example: A disallow rule in your robots.txt file blocks search engines from accessing your site.

2. URL Errors

URL errors are crawl issues that affect specific pages on your site, rather than the entire website. These errors can prevent important pages from being indexed, reducing your overall search visibility. Here are the most common types:

a. 404 Errors

These occur when a page is missing or has been deleted without a proper redirect. When a user or search engine tries to access the page, they receive a “404 Not Found” response. This can happen due to:

• Broken internal or external links
• Incorrect URL structures
• Deleted pages without proper redirects

b. Soft 404 Errors

Soft 404 errors happen when a page returns a 200 OK status code (indicating success) but displays content that makes Google think it should be a 404 error. This often occurs due to:

• Thin Content: Pages with insufficient or low-value content, like empty internal search results.
• Low-Quality or Duplicate Content: Placeholder pages, “lorem ipsum” content, or duplicates without canonical URLs.
• JavaScript Issues: Problems loading JavaScript resources.
• Other Reasons: Missing files or broken database connections.

Example: A product page showing “Sorry, this product is out of stock” without offering alternatives.

c. 403 Forbidden Errors

A 403 error occurs when access to a page is denied, often due to permission settings on the server. For example, A user tries to access a restricted page and receives a “403 Forbidden” message.

d. Redirect Loops

These happen when a page is stuck in a continuous redirect cycle, either pointing back to itself or creating an endless loop. This can confuse search engines and lead to a poor user experience.

Fixing these URL errors can improve your site’s crawlability and ensure important pages get indexed properly.

How to Find Crawl Errors

Finding and fixing crawl errors is crucial for maintaining a healthy and accessible website. 

Google Search Console

Here’s a step-by-step guide to help you identify crawl errors using Google Search Console (GSC):

Step 1: Access Google Search Console

1. Sign In: Log in to your Google Search Console account.
2. Select Property: Choose the website property you want to inspect.

Step 2: Navigate to the Indexing Report

1. Go to indexing: In the left-hand sidebar, click on “pages” under the “Indexing” section.
2. Overview: The indexing report provides an overview of errors, valid pages, warnings, and exclusions.

Step 3: Identify Crawl Errors

1. Error Categories 

Review the report and look for errors listed under:

• Errors: Critical issues that need immediate attention.
• Valid with Warnings: Pages that have issues but are still indexed.
• Valid: Successfully indexed pages without any issues.
• Excluded: Pages that are intentionally not indexed or have specific issues preventing indexing.

2. Types of Errors

• Site Errors: Affect the entire website, such as DNS errors or server errors.
• URL Errors: Specific to individual pages, such as 404 errors or access denied (403) errors.

Step 4: Detailed Error Analysis

1. Click on Errors: Click on the specific error type to view detailed information.
2. Inspect URLs: For each error, GSC will list the affected URLs. Click on a URL to see more details and recommendations.

Step 5: Use the URL Inspection Tool

1. Inspect URLs: Copy the problematic URL and use the URL Inspection tool to test and analyze it.
2. Request Indexing: Once the issue is resolved, request indexing to prompt Google to recrawl the page.

Semrush’s Site Audit

Tools like Semrush offer comprehensive site audits and detailed error reports. Here’s a general process you can follow with these tools:

• Perform a Site Audit: Use the tool’s site audit feature to scan your website. Enter your domain and configure the settings as needed.
• Review Error Reports: Analyze the detailed reports generated by the tool. Look for broken links, missing pages, and other crawl errors.
• Follow Recommendations: Most tools provide actionable insights and recommendations for fixing identified issues.
• Monitor Regularly: Use these tools to perform regular site audits to ensure your site remains free of crawl errors.

You can use these additional tools along with Google Search Console to get a better view of your site’s health. This helps you stay on top of issues that could affect your SEO performance.

How to Fix Crawl Errors

Once you’ve identified crawl errors on your site, the next step is to fix them to ensure your pages are properly indexed and ranked. Here’s how to tackle the most common types:

1. Fixing 404 Errors

404 errors occur when a page on your site can’t be found. Here’s how to fix them:

• Use 301 Redirects: Permanently redirect the old, broken URL to a relevant, existing page. This passes some of the original page’s authority to the new URL.
• Use 302 Redirects for Temporary Moves: Use these if the page will come back later, but avoid overusing them as they don’t pass as much link equity.
• Fix Broken Links: Identify and correct any internal links pointing to the missing page.

Ways to Deploy Redirects:

1. Plugins (WordPress): Use tools like Redirection, Yoast SEO (premium), or 301 Redirects to manage URL changes.
2. Server Configuration: Add redirects directly in your server configuration files, like .htaccess for Apache servers.
3. CMS Redirect Tools: Use built-in tools if you’re using platforms like Wix or Shopify.

2. Fixing Broken Links

Broken links can also trigger 404 errors and disrupt the user experience. Here’s how to fix them:

• Identify Broken Links: Use site audit tools like Semrush, Ahrefs, or Screaming Frog to find broken internal and external links.
• Correct Typos: Fix any spelling mistakes in URLs that are causing broken links.
• Update or Remove Outdated Links: Replace broken links with active pages or remove them if no relevant replacement exists.
• Use 301 Redirects: If a page has been permanently removed, redirect the broken link to the most relevant page.

3. Fixing Robots.txt Errors

Your robots.txt file tells search engines which pages to crawl and which to ignore. Here’s how to fix common robots.txt errors:

• Check for Format Errors: Use site audit tools to find any formatting issues.
• Correct Blocked Pages: Ensure important pages are not accidentally blocked.
• Test Your File: Use Google Search Console’s robots.txt tester to validate your file.
• Keep It Updated: Regularly review your robots.txt file to reflect changes in your site structure.

Concluding Thoughts

Fixing crawl errors is essential for maintaining a healthy, search-friendly website. These errors can prevent search engines from indexing your pages, leading to lost visibility and lower rankings. 

By regularly auditing your site, correcting broken links, updating your robots.txt file, and implementing proper redirects, you can ensure that search engines can fully access and understand your content. This, in turn, helps you stay competitive in search results and deliver a better experience for your visitors. 

Remember, proactive maintenance is key to keeping your site error-free and optimized for search engines.

Frequently Asked Questions