IP Canonicalization Checker
IP canonicalization means your server's IP address redirects to your domain name, not the other way around. Duplicate content at your IP breaks SEO. Use this free tool to check if your website has IP canonicalization issues and get clear steps to fix them.
IP Canonicalization Checker Tool
Enter your website URL below. The tool resolves your domain to its IP address and checks whether a direct HTTP request to that IP redirects back to your domain name.
What Is IP Canonicalization?
Every website server has a numeric IP address, such as 203.0.113.45. When someone visits http://203.0.113.45/ directly, they may see the same website content as https://example.com.
This creates a duplicate content problem. Search engine crawlers may index your website under both the IP address and the domain name, splitting link authority and confusing ranking signals.
http://203.0.113.45/
Shows website content directly
http://203.0.113.45/
301 redirect to https://example.com
IP canonicalization is a server-level configuration that ensures any direct IP request is permanently redirected (301) to your canonical domain. It is a technical SEO best practice recommended by Google.
Why IP Canonicalization Matters for SEO
Most websites do not attract a lot of direct IP traffic, but leaving the issue unconfigured creates avoidable SEO risks that compound over time.
Search engines may crawl and cache your pages under the IP address, creating duplicate versions of your content. This splits ranking signals between the IP version and the domain version.
If any backlinks or internal links point to the IP address instead of the domain, the link equity is not passed to the canonical URL. A 301 redirect consolidates all equity to the domain version.
Googlebot may waste crawl budget indexing IP-based URLs instead of spending that budget on important domain pages. For larger websites, this directly affects how many pages get indexed.
IP-based access often bypasses HTTPS, presenting insecure HTTP content. Modern browsers show warnings, which reduces user trust and can affect your Core Web Vitals data in Search Console.
How to Check IP Canonicalization Manually
If you want to verify manually without using the tool above, follow these steps.
Run nslookup example.com or ping example.com in your terminal. Note the numeric IP address returned, for example 203.0.113.45.
Visit http://[your-ip]/ in a browser (use HTTP, not HTTPS, as the IP certificate will be invalid). Or run curl -I http://203.0.113.45/ in your terminal.
Look for a 301 Moved Permanently or 302 Found redirect with a Location header pointing to your domain. A 301 is ideal as it passes full link equity. If you see website content instead of a redirect, IP canonicalization is not configured.
How to Fix IP Canonicalization
The fix depends on your web server. In all cases, the goal is to add a redirect rule that sends requests arriving via the IP address to your canonical domain with a 301 status.
RewriteEngine On
RewriteCond %{HTTP_HOST} !^example\.com$ [NC]
RewriteRule ^ https://example.com%{REQUEST_URI} [R=301,L]
Add to your .htaccess file. Replace example.com with your domain. This redirects any request where the Host header is not your domain.
server {
listen 80 default_server;
server_name _;
return 301 https://example.com$request_uri;
}
Add a catch-all default_server block that redirects any unmatched hostname (including direct IP access) to your canonical domain.
If your website is behind Cloudflare, IP-direct requests typically never reach your origin server since Cloudflare proxies all traffic under your domain. However, confirm that Cloudflare's SSL is set to Full (strict) and that you have HTTPS redirect enabled in the SSL/TLS › Edge Certificates settings.
On shared hosting, add the Apache rule above to your .htaccess file in the public_html directory. If your host does not allow .htaccess rewrite rules, contact your host support and ask them to configure a 301 redirect from the server IP to your domain at the server block level.
After applying the fix, use the checker tool at the top of this page to confirm the redirect is working. It may take a few minutes for server changes to take effect. For Cloudflare users, also clear the Cloudflare cache after making changes.
What This Checker Actually Tests
Understanding the test helps you interpret the result correctly, especially for servers with HTTPS-only configurations.
The tool performs a DNS lookup for your domain to find the primary A record (IPv4 address). If the DNS lookup fails, the check cannot continue.
The tool sends an HTTP GET request directly to the IP address (not HTTPS, since IP-based HTTPS certificate validation would fail). It sends no Host header so the server must handle the bare IP request.
If the response is a 3xx redirect to your domain — pass. If the response returns content (2xx) — fail (IP is serving content). If the connection is refused or times out — this usually means your firewall blocks direct IP access, which is a safe outcome but cannot be confirmed as a proper redirect.
Frequently Asked Questions
Is IP canonicalization a Google ranking factor?
IP canonicalization is not a direct ranking factor but it prevents duplicate content issues that do affect rankings. Google's John Mueller has confirmed that duplicate content at IP addresses is a real indexing concern, particularly for older websites that have accumulated backlinks to their IP address.
My server blocks direct IP access — is that enough?
Blocking or refusing direct IP connections is better than serving content, but a 301 redirect is the correct SEO solution. Blocking (connection refused) means search engines cannot crawl the IP version, but any existing backlinks pointing to the IP address will not pass equity to your domain. A 301 redirect consolidates both crawlability and link equity.
Does IP canonicalization affect HTTPS websites?
Yes. Most IP canonicalization checks use HTTP (not HTTPS) to the IP address, because visiting an IP address over HTTPS fails SSL certificate validation. Your server should redirect HTTP IP requests to your HTTPS domain. The redirect chain would be: http://[ip]/ → 301 → https://example.com/.
What is the difference between IP canonicalization and www canonicalization?
IP canonicalization redirects your numeric IP address to your domain name. WWW canonicalization ensures only one version of your domain is used — either www.example.com or example.com — with the other redirecting to the preferred version. Both issues resolve to the same concept: one canonical URL per page.
I use a CDN — do I still need to check IP canonicalization?
If you use a CDN like Cloudflare with full proxying enabled, direct IP access reaches CDN edge servers, not your origin. Cloudflare handles this at the edge and typically does not expose your origin IP. However, if your origin IP is publicly known or exposed (for example, via MX records or old DNS records), check both the CDN edge and origin IP directly.
The checker says "connection refused" — do I need to fix anything?
Connection refused means your server (or firewall) is not accepting connections on port 80 directly to the IP. This is common for HTTPS-only servers. It is a better outcome than serving content, but a proper 301 redirect is the recommended setup. To fix it fully, configure your web server to accept and redirect HTTP port-80 requests from the IP to your canonical HTTPS domain.
Fix More Than Just IP Canonicalization
IP canonicalization is one of many technical SEO signals that affect how search engines crawl and index your website. CheckSEO gives you a full technical audit covering index coverage, sitemap, robots.txt, content quality, and internal links — all in one free report.