Hreflang & International SEO
TL;DR
Hreflang tags tell Google which language and region each page targets, preventing the wrong version from showing in the wrong country's search results.
Explain Simply
If your website has a Vietnamese version and an English version, hreflang is like putting a flag on each one so Google shows the Vietnamese version to people in Vietnam and the English one to people in the US.
Hreflang (rel="alternate" hreflang="x") is an HTML attribute that specifies the language and optional regional targeting of a page. It helps search engines serve the correct language version to users in different countries.
Implementation methods: HTML link tags in
, HTTP headers (for PDFs and non-HTML), or XML sitemap entries. Each page must reference all its language alternatives including itself (self-referencing). The x-default value serves as a fallback for unmatched languages.Common mistakes: missing return links (page A references B but B doesn't reference A), incorrect language codes (using 'uk' for Ukrainian instead of 'ua'), mixing implementation methods, and not including self-referencing tags. Google ignores hreflang if any errors are detected in the set.
⚡Why It Matters
Without hreflang, Google may show your English page to Vietnamese users or vice versa. Incorrect international targeting can reduce organic traffic by 30-50% in affected regions. For multilingual sites, hreflang is essential to prevent self-cannibalization.
🔍How AiSEO Checks
AiSEO validates hreflang tag syntax, checks return link reciprocity, verifies language/region codes against ISO standards, and detects conflicting signals between hreflang and canonical tags.
AiSEO Score Impact
Up to 2 points in the Technical category (25% of total score)
Fix Difficulty
Editor: N/A | Developer: Medium | AI Agent: Medium