WCAG 3.1.2 Language of Parts

Success Criterion 3.1.2 requires that the human language of each passage or phrase can be programmatically determined when it differs from the page's overall default language. It's a Level AA criterion under Guideline 3.1 (Readable) — the mixed-language extension of 3.1.1's page-level requirement.

What this covers beyond the page-level lang attribute

3.1.1 handles the page's overall default language. This criterion handles the case where content genuinely switches languages within a page — a French idiom quoted in an English article, a Spanish product name in an English product listing, a bilingual page presenting the same content in two languages side by side.

<p>The French phrase <span lang="fr">c'est la vie</span> has no exact English equivalent.</p>

Why the screen reader impact is significant

Without marking the language switch, a screen reader continues applying its current pronunciation engine to the foreign-language text — reading French words with English phonetic rules produces something between mildly wrong and completely unintelligible, similar to the core problem 3.1.1 addresses at the page level, just localized to a smaller passage.

Practical scope: when this actually applies

This criterion isn't about single foreign loanwords that have become part of common English usage (words like "café" or "pasta" don't need to be marked) — it's about genuine passages or phrases meaningfully in another language. Proper nouns (a person's name, a place name) are also generally exempt, since they're typically pronounced consistently regardless of surrounding language.

Where this most commonly matters

Content-heavy sites that regularly quote, translate, or reference multiple languages — news sites, academic or reference content, multilingual product catalogs — are the most likely to have real 3.1.2 obligations. A typical single-language business site with only occasional foreign proper nouns or borrowed terms usually has little to address here beyond getting the page-level lang attribute right.

Official references

• W3C Technique H58