Hreflang Checker

The hreflang checker extension analyzes multilingual page signals for a given URL or set of URLs. It validates that language codes (ISO 639-1) and region codes (ISO 3166-1 alpha-2) are used correctly, that all language variants referenced by hreflang exist and point to valid URLs, and that x-default is present when appropriate. Target users include SEO specialists, web developers, and content managers responsible for international sites. It is most useful during site launches, migrations, multilingual content audits, and ongoing quality checks.

Core logic includes extracting hreflang attributes from HTML or sitemap inputs, normalizing codes, and cross-checking against the site's canonical structure. It flags missing or duplicate hreflang values, detects inconsistent mappings across alternate pages, validates URL syntax and host consistency, and reports any non-target URLs. Optional features support bulk assessment via sitemap lists and exportable reports suitable for stakeholder reviews. The tool emphasizes standards adherence and minimizes crawl inefficiency.

Outputs provide a structured assessment that lists issues, suggested corrections, and confidence scores. It helps teams fix misaligned language targeting, reduce duplicate content signals, and improve global indexation. By aligning with Google guidelines and ISO code sets, it enables scalable multilingual governance, supports complex site hierarchies, and aids in decision making for localization strategy.