Arclab® Website Analyzer

Search Your Website for Duplicate HTML Content
Find All Duplicate Pages without a Canonical Link Tag

What means "Duplicate HTML Content"?

In this context, "Duplicate HTML Content" means that exactly the same HTML page can be accessed under 2 different URIs. For this purpose, a checksum is created for each HTML page and all pages found during the scan are compared with each other.

Excepted from the report are:

HTML pages that already contain a "rel=canonical" link tag in the HTML header.
The folder "/" and the default page name e.g. "index.html" in the folder.
In the "Website Settings" you can add or remove default page names if you want to include them in the report.

How can I Find "Duplicate HTML Content" on My Website?

Troubleshooting is easy with Arclab® Website Analyzer. First, let the program scan your website.
After the scan of your website is completed, you will receive a detailed report containing all errors found on your website and other information:

Website Analyzer Report

In the "Duplicate HTML Content" line, click "Show Details" to display details about the errors:

Details: Duplicate HTML Content

At least 2 HTML pages listed under (A) contain exactly the same content or have the same checksum (B).
This error can occur, for example, if you have renamed pages but the old page is still on the server and there are still links to the old page.
However, if this is intentional or for technical reasons, you should insert a "rel=canonical" link tag in the HTML header to avoid negative effects on the search results.

"rel=Canonical" HTML Header Link Tag

The "rel=canonical" link tag in the HTML header is used to prevent duplicate content issues in search engine optimization (SEO) by indicating the "canonical" or "preferred" version of a web page.

Sample:

<!doctype html>
<html lang="en">
<head>
...
<link rel="canonical" href="https://www.yourdomain.tld/some-page.html">
...
</head>

...

</html>