Canonical URL

A tag that tells crawlers which URL is the definitive version when duplicate or similar pages exist.

Definition

A canonical URL is declared with a `<link rel="canonical" href="...">` tag in a page's `<head>`. It signals the preferred URL when the same content is accessible at multiple addresses — for example, with and without trailing slashes, with query parameters, or across HTTP and HTTPS. Crawlers use the canonical URL to consolidate authority signals.

Why it matters for AI visibility

When signals are split across duplicates, answer engines have a harder time identifying which version of a page to trust and cite. A clear canonical removes that ambiguity and consolidates ranking and citation potential.

XML SitemapA structured file listing the canonical URLs on your site so crawlers can discover them efficiently.

Structured Data (JSON-LD)Machine-readable markup that gives AI systems explicit facts about your organization, products, and content.

↗ Checklist: Canonical URLsCanonical tags tell crawlers which URL should collect authority when duplicate or similar pages exist.

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