If you publish in more than one language or region, hreflang decides whether the right version reaches the right user — and it's the single most error-prone area in technical SEO. Here's how it works and what breaks it.
hreflang only works when every page in a language group references every other version correctly, reciprocally, and with valid codes. One missing return tag or typo silently breaks the whole cluster.
Get hreflang right and search engines serve your Turkish page to Turkish users and your English page to English users, with no duplicate-content confusion. Get it wrong and you can end up with the wrong-language result ranking, or your versions competing against each other. The explainer below covers the complete rules: self-references, reciprocal return tags, valid language and region codes, x-default, and keeping every target canonical and returning 200.
The complete, error-by-error guide to getting hreflang right.
Self-references, reciprocal return tags, valid language/region codes, x-default, and keeping every referenced URL canonical and 200. Every hreflang error the audit flags, with the fix.
Grounded in the real checks the crawler runs.
Invalid hreflang language/region codes · missing x-default · multiple hreflang entries per language · broken hreflang targets (non-200) · hreflang pointing to a non-canonical URL · missing reciprocal (return) hreflang · missing self-reference hreflang · hreflang language mismatch with the page's actual language · html lang attribute missing or invalid · hreflang group members not crawled. Localization issues frequently overlap with Indexability, since every hreflang target must also be canonical and indexable.
Free to start. Find broken return tags, invalid codes and missing x-defaults across every locale.
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