Choose the version users should share
Use the clean, stable URL you want in search results and analytics. Common duplicates come from tracking parameters, print views, case differences, trailing-slash variations and products exposed through several categories.
A self-referencing canonical is often useful because it makes the page’s preference explicit and protects against incidental parameters.
Make supporting signals agree
Internal links, redirects, sitemap entries and hreflang references should normally point to the canonical version. If a page declares one URL while the site consistently links to another, crawlers must resolve the contradiction.
Do not canonicalise genuinely different pages simply because one performs better. The destination should be an appropriate substitute for the content being consolidated.
Use one absolute declaration
An absolute HTTPS URL is easier to inspect and less vulnerable to an unexpected base URL. Render one canonical tag rather than allowing several plugins or templates to compete.
<link rel="canonical" href="https://example.com/delivery/" />
// Next.js App Router
export const metadata = {
alternates: { canonical: "/delivery/" },
};Canonical is a hint
Search engines may select another URL when redirects, content, links or availability provide stronger evidence. Diagnose the whole URL system instead of treating the tag as a forced instruction.