> For the complete documentation index, see [llms.txt](https://doc.batch.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.batch.com/developer/sdk/react-native/profile-data/custom-locale.md).

# Custom region/language

Batch allows you to set a custom region or a custom language that will override the value detected by the SDK. By default, Batch collects the language and the country of your users' devices.

Setting a custom region/language is useful if:

* You don't want to use the values detected by Batch.
* Your users can choose their own language or region for localization purposes.

![Custom locale](/files/JfgYJWbzQUl3TlW0U7Of)

**Writing custom region/language**

```javascript
import { BatchProfile } from '@batch.com/react-native-plugin';

BatchProfile.editor()
    .setLanguage("en") // Language must be 2 chars, lowercase, ISO 639 formatted
    .setRegion("US") // Region must be 2 chars, uppercase, ISO 3166 formatted
    .save();
```

**Reading custom region/language**

Keep in mind that the data returned is only about your installation and not your Profile since it may be updated from another source.

```js
import { BatchUser } from '@batch.com/react-native-plugin';

// Result might be 'undefined' if Batch isn't started or if no override has been set
const language = await BatchUser.getLanguage();
const region = await BatchUser.getRegion();
```


---

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