1.8 URL structure & internationalisationHighVerified
Multiple URLs serving identical content
When www and non-www, http and https, or parameter variants all serve the same page, Google sees several copies and has to guess the real one. I collapse them to a single canonical URL.
What it is
www/non-www, http/https, params all live.
Why it matters
Classic duplication splitting authority.
How to fix it
Choose a canonical form; redirect and canonicalise the rest.
How to find it on your site
- Test www vs non-www, http vs https, and common parameter variants for the same page.
- Note which ones return 200 rather than redirecting.
- Pick one canonical form and 301-redirect all the others to it.
- Make canonical tags and internal links use the chosen form.
Cross-reference to ranking and citation factors
Duplicate URLs split ranking and citation signals across copies. Consolidating them onto one canonical concentrates the value.
Impact
Medium-high. Direct.
Evidence
Consolidate duplicate URLs to one canonical. Google Search Central, Consolidate duplicate URLs (canonicalization); Google Search Central, Keep a simple URL structure
Sources