Rel=Canonical should be used whenever you post duplicate content (from your site, or elsewhere.)
It’s a “soft redirect”, without redirecting the user. Links to both URLs now count as the single, canonical version of the URL. So your site isn’t penalized for duplicate content.
Get a Free Instant SEO Audit
- Tells google where the original is
- Code Snippet (place in HTML Head): <link rel=”canonical” href=”http://example.com/wordpress/seo-plugin/” />
- It’s also available through Yoast SEO , and some SEO tools like this – screenshot of where: