Search and SEO
What is Duplicate content?
Duplicate content is substantially identical content available at more than one URL, on your own site or across sites. There is no penalty for it in ordinary cases — the cost is that signals get split and the engine picks a canonical version that may not be the one you wanted.
Also called: content duplication
Internal duplication
- Trailing-slash and non-slash variants both returning 200
- HTTP and HTTPS, or www and non-www, both resolving
- Tracking parameters creating unique URLs
- One product reachable through several category paths
- Print or AMP versions with no canonical
External duplication
Publishing the manufacturer description that two hundred other stores also published is not a penalty — it is a competition problem. The engine has no reason to prefer your copy, so it prefers whoever has more authority.
The fix
Canonicalise deliberately, redirect variants in a single hop, and rewrite the descriptions on the products that actually sell. Rewriting twenty properly beats rewriting two hundred badly.
Where this is covered in depth
A definition can only go so far. Technical SEO, in the order the problems actually block you covers this properly — 4 minutes, free, no email required.
Who wrote this
Anas Bin Masud builds e-commerce sites and does technical SEO for businesses in the UK, Canada and Pakistan. These definitions come from client work rather than from a content brief — where an entry describes a mistake, it is usually one found on a real site. More about how I work.