Duplicate content
What is duplicate content?
Duplicate content is identical or nearly identical text that can be reached at more than one address, on one site or across several. Google does not penalise it by default; it picks one version to show and filters out the rest. A penalty follows only when the copying is meant to manipulate results, such as republishing other sites’ text wholesale as your own.
Example
An online lighting shop lists 1,200 products. Each one opens at three addresses — through its category, through its brand and on its own — and the colour and wattage filters add more addresses with parameters. Google has to crawl more than 3,600 URLs to find 1,200 pages, then decide for itself which version is the main one. On top of that, the descriptions come straight from the supplier: the same text sits in dozens of other shops selling the same lamps.
The repair has two halves. The technical half: every product gets one permanent address, the other versions 301-redirect to it or point to it with a canonical tag, and internal links go only to the main version. The content half: the best-selling products get descriptions of their own, with the details a buyer looks for and the supplier leaves out.
Why it matters for a business
Duplication rarely brings a penalty, but it nearly always costs something. Signals — links, clicks, shares — split across several addresses instead of adding up on one. Google may choose a main version you did not want. On a large site, crawling is spent on copies while new products wait. And when your description is the same as twenty other shops’, the search engine has no reason to show yours.
Not everything alike is duplication. A translation into another language is a separate page, and a quotation with its source named is normal. The problem is text that adds nothing.
What to ask
- At how many addresses does the same product or page open?
- What does the indexing report in Search Console say about the pages Google treats as duplicates?
- Which descriptions are copied from the supplier, and which of them are worth rewriting first?
- Is the staging copy of the site closed to search engines?
Finding duplicate content and putting the addresses in order is part of the technical side of our SEO work.