How to fix valid lang on Webflow
Add a valid BCP 47 language code to every `lang` attribute on your pages so assistive technologies can read content in the correct language.
Steps for Webflow
- In the Webflow Designer, go to Project Settings (the gear icon) → Localization (or General) and set the primary locale/language. Webflow uses this to populate `<html lang>`.
- Alternatively, open Project Settings → Custom Code → add a `<script>` in Head Code that sets `document.documentElement.lang = 'en';` only if Webflow does not expose a direct language field for your plan — but prefer the Localization setting.
- For Webflow Localization (paid feature): Settings → Localization → add/edit each locale and ensure its language code is a valid BCP 47 tag. Webflow sets `lang` per locale automatically.
- For any Embed components (HTML Embed blocks) in the canvas that contain a `lang` attribute, click the block, open the HTML editor, and correct the value.
- Publish the site and verify with the axe browser extension.
<html lang="en">
<!-- For a page in US English -->
<html lang="fr">
<!-- For a page primarily in French -->
<!-- Inline language switch for a passage in Spanish on an English page -->
<p lang="es">Bienvenido a nuestra tienda.</p>
<!-- Region-specific variant -->
<html lang="pt-BR">
<!-- Brazilian Portuguese -->What is valid lang?
Every HTML page has a `lang` attribute on the `<html>` tag (e.g. `<html lang="en">`) that tells browsers and assistive technologies what language the page is written in. When a page contains a passage in a *different* language, that section should also carry its own `lang` attribute (e.g. `<p lang="fr">`). The value must be a valid BCP 47 language tag — a standardised code like `en`, `en-US`, `fr`, `de`, or `zh-Hans`. An empty, misspelled, or made-up value (such as `lang=""` or `lang="english"`) fails WCAG Success Criterion 3.1.2 (Language of Parts).
Screen readers like JAWS, NVDA, and VoiceOver automatically switch their text-to-speech voice and pronunciation rules based on the `lang` attribute. If the value is missing or invalid, the reader mispronounces words — sometimes so badly that the content becomes completely unintelligible to blind or low-vision shoppers. Beyond accessibility, WCAG 3.1.2 is a Level AA requirement, meaning failing it exposes your store to legal risk under laws such as the ADA in the US, the European Accessibility Act, and equivalent legislation elsewhere. Google also uses language signals to serve your pages to the right audiences, so correct `lang` values support your international SEO.
See the complete Valid lang guide for every platform and the full background.
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