> For the complete documentation index, see [llms.txt](https://docs.userlane.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.userlane.com/developer-reference/userlane-language-detection.md).

# Userlane language detection

Language detection priorities and how to set the language explicitly with the lang command.

## About language detection

Userlane detects the language of the application and of the user's browser, then matches the user's language preference.

## Detection priorities

Userlane resolves the language in this order:

1. The language set by the `lang` command in the application.
2. The language settings in the Userlane Portal.
3. The HTML `lang` attribute.
4. Meta information.
5. The browser language.
6. The default language defined in the Userlane Portal.

{% hint style="info" %}
Where the application hard-codes the language tag in its HTML, contact the customer value team. In those cases the detection can be adjusted so that the end user's browser language takes priority over the application's language.
{% endhint %}

## Define a specific language

To make Userlane always use the same language as the application, set the language explicitly with the `lang` command. This is useful where the application offers a language setting but does not declare its language in the standard HTML `lang` attribute.

```javascript
// set the language of Userlane
Userlane('lang', 'language_code');
```

The language code is either a two-letter code, such as `en` or `de`, or a five-letter code, such as `en-us` or `en-gb`.

## Best practices

**Match the language codes exactly.** The code used in the command has to match the language key that was used when the language was created in the Portal.

**Publish the language first.** A language passed via the `lang` command has to exist and be public in the Userlane Portal. Otherwise Userlane falls back to the default language.

**Check which language the Editor opens in.** The Editor opens in the last language worked in. That makes it easy to continue editing, but it also means edits can land in the wrong language after switching, and it explains why the Assistant appears in a particular language.

## Relevant articles

{% content-ref url="/pages/cg5g8Xki3RfJej7DhphW" %}
[Content operations](/assistance/content-operations.md)
{% endcontent-ref %}

{% content-ref url="/pages/JaoydeD5UPCYFS9NuupA" %}
[Quick reference of commands](/developer-reference/quick-reference-of-commands.md)
{% endcontent-ref %}

{% content-ref url="/pages/brm1JWKM3yHqhKU1n5G2" %}
[A tour of the Editor](/assistance/a-tour-of-the-editor.md)
{% endcontent-ref %}


---

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