# How do I avoid duplicate content when redesigning a website? > You avoid duplicate content in a redesign by making sure only one version of each page is indexable. The three usual culprits are an indexed staging site competing with live, the old and new sites both being reachable during a migration, and URL variants (www vs non-www, http vs https, trailing slashes) serving the same content at multiple addresses. The fixes match the causes: keep staging noindexed, 301 the old site or domain to the new, and canonicalize URL variants to one preferred form. WPBuildAI scans the site for indexable duplicates so you catch them before Google does. Source: https://wpbuildai.com/avoid-duplicate-content-redesign-website/ By lawrence-arya ยท 2026-06-26 --- You avoid duplicate content when redesigning a website by making sure only one version of each page is indexable. Duplicate content is not usually about copied text; in a redesign it is about the same content being reachable at more than one address, which splits ranking signals and confuses search engines about which version to show. Three culprits cause almost all of it: an indexed staging site competing with the live one, the old and new sites both staying reachable during a migration, and URL variants (www versus non-www, http versus https, trailing slashes) serving the same page at several addresses. The fixes map directly to the causes, and they are all things you can check before launch. WPBuildAI scans the site for indexable duplicates so you catch them before Google does. The most persistent duplicates live on host variants, which is why Google's June 2026 guidance asks you to file Change of Address requests for [all subdomains and both the www and non-www variants](https://searchengineland.com/for-site-moves-specify-all-domain-variants-with-googles-change-of-address-tool-480552) even when you believe those variants are dormant. ## What causes duplicate content in a redesign Duplicate content in a redesign is a question of indexable copies. Whenever the same content is available at two addresses that Google can both index, you have a duplicate, and Google has to guess which to rank, often splitting the signals between them. Google's guidance on [consolidating duplicate URLs](https://developers.google.com/search/docs/crawling-indexing/consolidate-duplicate-urls) describes how it picks a canonical version, but you do not want to leave that to chance during a migration. The goal is simple to state: for every piece of content, exactly one indexable URL. The three sections below are the ways a redesign breaks that rule. ## Cause 1: an indexed staging site The most damaging duplicate is an indexed staging site. Staging is a full copy of your site, so if Google can crawl it, you have two complete copies of everything competing with each other. This happens when staging is left without protection, on a public subdomain with no block. The fix is to keep staging noindexed while you build, using the noindex mechanism in Google's [block indexing guidance](https://developers.google.com/search/docs/crawling-indexing/block-indexing), and ideally behind a password too. The twist, covered in [what is a staging site](/what-is-staging-site-wordpress-deployment/), is to remember to remove that noindex from the live site at launch, or you swap a duplicate problem for a deindexed one. ## Cause 2: the old and new site both live During a migration, the old and new sites can briefly both be reachable, especially across a domain or platform change, creating two live copies. If both stay indexable, they compete. The fix is to make the old version point to the new one with 301 redirects, per Google's [site move guidance](https://developers.google.com/search/docs/crawling-indexing/site-move-with-url-changes) and [redirects documentation](https://developers.google.com/search/docs/crawling-indexing/301-redirects), so the old URLs resolve to the new and only one version remains indexable. The redirect both removes the duplicate and transfers the old version's equity, which is why it is the right tool rather than simply deleting the old site. ## Cause 3: URL variants (www, https, trailing slash) The quietest duplicates are URL variants of the same page. The same content can be served at www and non-www, at http and https, and with and without a trailing slash, four or more addresses for one page. A redesign is a common moment for these to multiply, when server config changes. The fix is canonicalization: pick one preferred form (for example, https non-www without a trailing slash), 301 the other variants to it, and set canonical tags pointing to the preferred URL, as in [consolidating duplicate URLs](https://developers.google.com/search/docs/crawling-indexing/consolidate-duplicate-urls). This collapses the variants into one indexable address. ## The fixes: noindex, canonical, redirect The three tools map to the three causes, and it helps to know which does what. Noindex removes a page from the index entirely, the right tool for staging. A 301 redirect sends one URL to another and passes equity, the right tool for old-to-new and for variant consolidation. A canonical tag tells Google which version to treat as primary when duplicates must coexist, the right tool when you cannot redirect but want to signal a preference. Used together, noindex on staging, 301 from old to new, and canonical to one variant, they ensure exactly one indexable version per page, which is the whole goal. ## A worked example A company redesigned its site on a new platform. Before launch, a scan found three duplicate risks: the staging subdomain was indexable, the new site briefly answered at both www and non-www, and the old URLs would remain live after the cutover. They noindexed staging and put it behind a password, set the new site to redirect non-www to www with a 301 and added canonical tags, and prepared 301s from every old URL to its new counterpart. At launch they removed the staging noindex and applied the redirects. Google saw exactly one version of each page, so no duplicate content arose and the rankings consolidated cleanly on the new site. ## Common mistakes - Leaving the staging site indexable, so it competes with live. - Deleting the old site instead of redirecting it, losing equity and leaving stray indexed URLs. - Ignoring www, https, and trailing-slash variants of the same page. - Carrying the staging noindex onto the live site at launch. - Relying on canonical tags alone where a 301 is the correct fix. ## Key points to remember You avoid duplicate content in a redesign by ensuring exactly one indexable version of each page. The three causes are an indexed staging site, the old and new sites both live, and URL variants (www, https, trailing slash). Fix them with the matching tool: noindex staging (and remove it at launch), 301 the old site or domain to the new, and canonicalize variants to one preferred URL with redirects and canonical tags. Do this before launch so Google never sees the duplicates. WPBuildAI scans the site for indexable duplicates so you catch them first. Send your site URL for a free duplicate-content check. Not affiliated with WordPress, Lovable, Webflow, Shopify, Wix, or Squarespace.