Badi Jones

Duplicate Content Cure is an extremely simple plugin that makes WordPress more Search Engine 
friendly (And therefore improving SEO). It does this by preventing search engine spiders/bots 
from accessing pages like Archives, Tags, and Categories, which tend to contain duplicated content 
from elsewhere on your site. This is achieved by adding nofollow, noindex to 
these problem pages.
Duplicate Content Cure doesn’t have a lot of features that other SEO plugins have, but 
it also is lightning fast by comparison.

Duplicate Content Cure

Duplicate content cure is a simple plugin that improves SEO by preventing search engines from indexing pages that contain duplicate content.

Freemius

AuditySEO

AuditySEO Canonical Manager gives you complete, granular control over the canonical URL of every page on your WordPress site: posts, pages, custom post type entries, taxonomy terms, archive pages, and even the pagination pages WordPress generates automatically.
Missing or incorrect canonical tags are one of the most common technical SEO problems on WordPress sites. They let search engines index duplicate versions of the same content, split your ranking signals across multiple URLs, and waste crawl budget on pages that should never compete for the same keywords. AuditySEO Canonical Manager fixes this at the source, so every URL on your site points search engines to the page you actually want ranked.
<h4>Free features</h4>
<ul>
<li>Lists pages, posts, custom post types, terms and archives in a dedicated AuditySEO Canonicals admin screen.</li>
<li>Shows the default canonical URL that WordPress (or your SEO plugin) would output for each item.</li>
<li>Detects content pagination created with the <code></code> tag.</li>
<li>Detects pagination of the posts page (<code>page_for_posts</code>) based on the number of published posts and <code>posts_per_page</code>.</li>
<li>Detects pagination of taxonomy term and archive listings.</li>
<li>Lets you set a custom canonical URL per item and per pagination page.</li>
<li>Applies your overrides through the canonical filters of WordPress core, Rank Math and Yoast SEO.</li>
<li>Rewrites the <code><link rel="canonical"></code> tag in the final HTML output as a fallback for themes, caches and plugins that print a canonical outside of those filters.</li>
<li>Imports and exports canonical overrides via CSV, with a dry-run preview before bulk changes are applied.</li>
<li>Validates canonical URLs when you save them (HTTP status, redirects, noindex, external domain) without blocking the save, and flags the affected item with the reason until it is fixed.</li>
<li>Filters the editor by status, override state and pagination.</li>
</ul>
<h4>Pro features</h4>
Upgrade to AuditySEO Canonical Manager Pro to unlock:
<ul>
<li>History & restore – every change to a canonical override is recorded with the user and date, and can be rolled back with one click.</li>
<li>Automatic canonical fixes, applied site-wide:
<ul>
<li>Replace pagination canonicals that point to page 1 with each page’s own self-referencing URL.</li>
<li>Strip tracking parameters (utm_*, gclid, fbclid, msclkid, and more).</li>
<li>Strip display-variant parameters (print, amp, output, format, replytocom, and more).</li>
<li>Force the canonical to always match the requested URL exactly, including its query string.</li>
</ul>
</li>
</ul>
The free version is fully functional on its own and does not require the Pro upgrade to manage canonical overrides, detect pagination, validate URLs or import/export CSV files.

AuditySEO Canonical Manager

Full control over canonical URLs for posts, pages, CPTs, taxonomy terms, archives and paginated pages, with validation, history and auto-fixes.

Duplicate Content Cure vs AuditySEO Canonical Manager