Definition
i18n SEO is the technical discipline that ensures a multilingual or multi-regional site is correctly understood and indexed by search engines for each language/region combination. This includes implementing hreflang tags, choosing URL structure (subdirectories, subdomains, or ccTLDs), managing duplicate content between language versions, configuring Search Console by country, geotargeting, and adapting sitemaps. Common mistakes include incorrect hreflang, poor-quality auto-translated content, and IP-based redirects that prevent Googlebot from seeing all versions. A successful i18n SEO strategy combines solid technical architecture with quality localized content.
Key Points
- Hreflang tags must be bidirectional and include an x-default
- Never auto-redirect based on IP (blocks Googlebot)
- Each language version should have its own sitemap
Practical Examples
i18n structure with subdirectories
An international SaaS site uses subdirectories (/fr/, /en/, /de/) with cross-linked hreflang tags on each page, a sitemap per language, and geographic targeting in Search Console.
IP redirect error
A site automatically redirects French visitors to /fr/ based on IP. Googlebot, crawling from the US, never sees the French version and only indexes the English version.
Frequently Asked Questions
Subdirectories (/fr/, /en/) are generally recommended as they inherit the main domain's authority. Subdomains (fr.example.com) are treated as separate sites by Google. ccTLDs (.fr, .de) provide the strongest geographic signal but are most expensive to maintain.
It's a best practice but not mandatory. Translated URLs (/fr/chaussures-homme/ vs /en/mens-shoes/) improve understanding by users and engines but add complexity. The essential thing is having correct hreflang tags.
Go Further with LemmiLink
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Last updated: 2026-02-07