Quick Reference
Element Code: HT-026
Issue: lang and xml:lang differ
Impact: Conflicting signals
Fix: Make them match
Detection: HTML validation
What Is This Issue?
If using both, they must match.
Why This Matters
Mismatch creates confusion.
How to Fix
- Match values or remove xml:lang
Tools
- HTML validator: Language check
TL;DR
Make lang and xml:lang match, or just use lang.
Claude Vincent is a technical SEO consultant focused on crawlability, rendering, and AI-search visibility. He writes the field guides and case studies at SEO ProCheck, with a bias toward the durable, unglamorous work that decides whether search engines and AI answer engines can actually read and cite a site.
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Technical SEO consulting and GEO strategy with 20 years of enterprise experience. Case studies, resources, and tools for search and AI visibility.
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