Duplicate content is the same or very similar content available at more than one URL, on your site or across sites. Google says it does not penalise duplicate content in itself, unless it is deceptive or manipulative; the real problems are that ranking signals get split across versions and Google may show a URL you did not choose. The fixes are to consolidate each piece of content to one canonical URL with redirects, canonical tags and consistent internal links, to write original text where you have copied it, and to handle syndication and scraping deliberately.
Common types and fixes
| Type | Example | Fix |
|---|---|---|
| Protocol and host variants | http and https, www and non-www | 301 redirects to one version |
| Trailing slash and case variants | /page and /page/ | Redirect to one pattern |
| Parameters | ?utm_source=, ?sort=, session IDs | Canonical tags; block crawl-wasting parameters |
| Printer or AMP versions | /print/page/ | Canonical to the main page, or remove |
| Product variants | Same product in several colours at separate URLs | One page with variant selection, or canonical to the main variant if the content is identical |
| Copied supplier or manufacturer text | The same description on hundreds of sites | Write original descriptions |
| Near-duplicate location or service pages | City pages differing only by name | Merge, or make each genuinely distinct |
| Staging or test sites indexed | staging.example.com | Password protection; remove from index |
For choosing between redirects, canonical tags and noindex, see robots.txt, noindex or canonical.
How to find duplicates
- Search Console’s Page indexing report: “Duplicate without user-selected canonical” and “Duplicate, Google chose different canonical than user”.
- A site crawl that reports duplicate titles, descriptions and near-duplicate content.
- URL Inspection, or the URL Inspection API, to see which canonical Google chose.
- A search for a distinctive sentence from your page in quotes, to find copies elsewhere.
Syndication
If you publish your articles on other sites, such as industry portals, Google advises that syndication partners should block indexing of the syndicated copy with noindex if you want your original to rank, since canonical tags across sites may not be followed. Agree this in advance, and ask for a link back to the original.
Scraped copies
Other sites copying your content usually do not outrank the original. If a copy causes problems, you can request removal under copyright law through Google’s legal removal process. Keeping your pages well linked and quickly indexed helps Google identify the original.
Boilerplate
Repeated headers, footers and disclaimers are normal and not a problem. Pages become duplicates when the main content itself is the same or nearly the same.
Frequently asked questions
Is there a duplicate content penalty?
Google says no, unless duplication is deceptive and intended to manipulate rankings. The practical cost is split signals and the wrong URL shown.
Is quoting other sources duplicate content?
Short, attributed quotes within original content are normal. Pages made mostly of copied text add no value.
Does duplicate content affect AI assistants?
When identical text exists on many sites, assistants have no reason to cite yours. Original information is what gets attributed. See information gain.
Sources
- Google Search Central, “Consolidate duplicate URLs”
- Google Search Central, guidance on syndicated content
- Google, legal removal requests (copyright)