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Bulk up to 100 • Accessibility + i18n signal

HTML Lang Attribute Checker

Paste URLs — we’ll fetch the page and detect <html lang="...">, xml:lang, and legacy content-language.

Paste up to 100 URLs (one per line)
Tip: html lang helps browsers, screen readers, and search engines understand the page language. Missing or wrong values can cause poor rendering and mixed-language signals.

Results

Host Lang signals HTTP Hops Time Issues
Run a check to see results here.
“Mismatch” means lang and xml:lang don’t match (usually you should keep them consistent).

Quick interpretation

The lang attribute is a small detail that helps accessibility and language detection.

  • OK html lang present and looks sane
  • Warning missing lang, odd format, mismatch, legacy meta
  • Error fetch errors, redirect loops, HTTP 4xx/5xx
Language signal

HTML lang attribute checker: find missing or inconsistent lang values

The lang attribute on the <html> element tells user agents what language the page is written in. It improves accessibility (screen readers), helps browsers pick correct fonts and hyphenation rules, and supports search engines with language understanding.

What this tool checks

  • html lang: missing, empty, or odd-looking formats
  • xml:lang: legacy attribute and mismatch checks
  • meta content-language: legacy signal (not recommended as the main method)
  • Fetch reliability: redirects, HTTP codes, and content-type

Best practices

  • Use a valid BCP 47 tag, like en, en-US, pt-BR.
  • If you use xml:lang, keep it the same as lang.
  • Don’t rely on meta http-equiv="content-language" — it’s a legacy approach.

FAQ

What is the HTML lang attribute?

The lang attribute on the <html> element tells browsers, assistive tech (screen readers), and search engines what language the page is written in. It’s a core accessibility and internationalization signal.

Is missing html lang a serious problem?

Yes — it can cause wrong pronunciation in screen readers, poor auto-translation behavior, and weaker language detection. It’s an easy technical fix with almost zero downside.

What is a “good” lang value?

Use a BCP 47 language tag like en, en-GB, fr, fr-BE, pt-BR. Avoid random words, empty values, or inconsistent casing/formatting.

What does “lang vs xml:lang mismatch” mean?

It means lang and xml:lang exist but differ. If you keep xml:lang at all (legacy), it should usually match lang.

Should I use xml:lang in modern HTML?

Usually no. For HTML documents, lang is the main attribute. xml:lang is legacy and mostly useful for XHTML or older setups.

Why is meta http-equiv="content-language" flagged as legacy?

Because it’s an older approach and not the primary method for declaring page language today. Rely on html lang first; keep the meta only if you have a specific legacy requirement.

Can a page have multiple languages?

Yes, but you still set html lang to the main language of the document. For mixed-language parts, you should set lang on specific elements (like a <span> or <p>) where the language changes.

Does lang affect SEO?

It’s mainly an accessibility/quality signal, but it helps language understanding and consistency. For international SEO, pair it with correct hreflang and clean canonicals.