Goal
Ensure assistive technologies can use the correct language rules for the page.
Success Criterion · WCAG 3.1.1
Language of Page
The default human language of each Web page can be programmatically determined.
Level AWCAG 2.0Understandable3.1 · Readable
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What to do
Set the default human language of each page (e.g., using `lang` on the root element).
Why it matters
Screen readers, translation tools, and spell checkers need the page language to pronounce and interpret text correctly.
Success criterion
What WCAG 3.1.1 requires
Summarized directly from the official Understanding document so teams can quote the requirement accurately.
The default human language of each Web page can be programmatically determined.
Intent
Why WCAG created this requirement
- Language metadata enables correct pronunciation, braille translation, and dictionary selection.
- This is foundational for multilingual sites and mixed-language content.
- It improves automated translation and indexing.
Benefits
Who gains when you pass
- Screen reader users hear correct pronunciation and language switching behavior.
- Braille users get correct contractions and translation tables.
- Users with cognitive disabilities benefit from more accurate speech output.
Why it matters
User impact when this criterion fails
Summaries drawn from the Understanding document help you socialize impact statements with product stakeholders.
Screen readers may mispronounce words if the language is not declared.
Braille output may be incorrect when language rules are unknown.
Translation tools may choose wrong defaults.
Overview
Every page must declare its primary language so assistive technologies can select correct pronunciation and processing rules. Commonly this is done with `lang` on the `<html>` element.
- Set `lang` on the root element for each page.
- Ensure the language code matches content (e.g., `en`, `en-US`, `es`, `fr`).
- Single-page apps must update language if locale changes.
Reference: All summaries and highlights originate from Understanding WCAG 3.1.1 and the W3C quick reference.
Fast facts
- Conformance level
- Level A
- WCAG version introduced
- WCAG 2.0
- Principle
- Understandable
- Guideline
- 3.1 · Readable
Examples
Make success tangible for teams
Share pass/fail snapshots to coach designers, engineers, QA, and content authors.
English page
Pass
<html lang="en">…</html>
Fail
No `lang` attribute set on the page.
Spanish page
Pass
<html lang="es">…</html>
Fail
<html lang="en">…</html> for a Spanish-only page.
Evidence to keep
Document conformance decisions
Capture artifacts for VPATs, procurement reviews, and regression testing.
- Document supported language tags and how they map to locales.
- Capture a sample of page source showing the `lang` attribute for audits.
Official resources
Deep dives and supporting material
Keep these links handy when writing acceptance criteria or responding to audits.
Implementation checklist
Capture progress and blockers
- Set the document language on each page/template.
- Ensure locale routing or language toggles update the `lang` attribute.
- Verify server-rendered pages output correct `lang` value.
- Document supported locales and their language tags.
Testing ideas
Prove conformance with evidence
- Inspect the DOM and confirm the root element has a correct `lang` value.
- Use a screen reader to verify pronunciation is appropriate for the language.
- Switch locales (if available) and confirm `lang` updates accordingly.
Related success criteria