Security & SEO

    Hreflang tag check

    Validates hreflang tags across your language variants — return-tag mismatches are the #1 cause of Google demoting international sites.

    Updated 2026-07-10
    1 min read
    hreflang
    seo
    international

    Quick answer#

    Lemwatch builds a cluster of every hreflang-tagged URL and confirms each URL has return tags pointing back to all the others (Google's requirement).

    What it checks#

  1. Valid ISO language + region codes
  2. Return tags are reciprocal
  3. x-default present
  4. All URLs in the cluster resolve to 200
  5. No language variant self-canonicalises to another

    6. Where to find it in Lemwatch#

    Site details → SEO → International.

    How to fix#

  6. Ensure every alternate URL includes hreflang links to every other alternate — including itself.
  7. Add hreflang="x-default" for your fallback URL.
  8. Fix any 404s in the cluster.
  9. Re-crawl.

    10. FAQ#

    Can I use hreflang in the sitemap instead?#

    Yes — Lemwatch checks both HTML tags and sitemap declarations.

    Do canonicals fight hreflang?#

    Yes — never canonicalise a language variant to another language.

    Related#

  10. Canonical tag check
  11. Robots.txt check
  12. Structured data check
    13. Was this article helpful?

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