1. Find duplicate URL paths
Check whether the same content loads with different protocol, host, trailing-slash, or tracking-parameter versions. Also review print pages, filtered views, or campaign URLs that repeat the same main content.
Compare the exact rendered page, not just similar-looking URLs. Query parameters used only for campaign tracking may leave the main content unchanged, while a genuinely different language or product page usually needs its own canonical.
2. Select the preferred page
Choose the version that should represent the content for users and search engines. The canonical target should be a real, accessible page with substantially equivalent content, not a convenient but unrelated destination.
Choose one stable HTTPS host and URL format, then confirm the target returns a successful response. A canonical should point to a useful equivalent page; it cannot repair a broken destination or turn unrelated content into duplicates.
3. Align the site signals
Use the preferred URL in internal links and the sitemap. Keep redirects and canonical annotations consistent; mixed signals make it harder for search engines to understand which version you want indexed.
Make the sitemap and ordinary links use the preferred address too. If an old URL has permanently moved, a server redirect can reinforce the transition; keep the canonical and redirect destination aligned.
4. Validate the result
Inspect page source for the canonical link and test that its destination loads successfully. Search Console may choose a different canonical based on its own signals, so check the indexed version instead of assuming the annotation guarantees selection.
After publishing, inspect both the preferred URL and a known alternate in Search Console. Compare the user-declared canonical with Google-selected canonical, and investigate conflicting redirects, internal links, or sitemap entries if they differ. For moved pages, also follow the redirect mapping guide so the destination signals agree.
Related official guidance: Google Search Central: canonicalization.