Duplicate content: causes and fixes

Duplicate content means the same or very similar content at more than one address. Search engines pick one to show and may ignore the others.

Common causes

• http and https, www and non-www versions all working.
• Trailing slashes and uppercase variants.
• Tracking and sorting parameters.
• Printer pages, tag archives, product variants.
• Copied manufacturer descriptions.

Fixes

• Redirect alternative hostnames to one version (www redirect checker).
• Canonical tags on parameter and variant pages.
• noindex on thin archives you do not need in search.
• Rewrite copied text in your own words.

Site audits flag duplicate titles, duplicate descriptions and duplicate content so you can find them across the site.

Duplicate content is not a penalty

Search engines do not punish ordinary duplicates; they choose one version to show. The problem is that they may choose the wrong one, and signals such as links are split between versions.

Content copied from you

If another site copies your content, search engines usually recognise the original. If a copy outranks you, contact the site owner, and make sure your page is indexed and well linked internally.

Near-duplicates

Pages that are mostly the same, such as product variants or location pages with only a city name changed, also count. Give each page something unique or combine them.

Syndication

If you republish your articles elsewhere, ask for a canonical tag pointing to your original, or publish a summary with a link instead of the full text.