> 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/android/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/SifTDeyDFZyAmSoHdhhk)

**Writing custom region/language**

{% tabs %}
{% tab title="Kotlin" %}

```kotlin
Batch.Profile.editor().apply {
   setLanguage("en") // Language must be 2 chars, lowercase, ISO 639 formatted
   setRegion("US") // Region must be 2 chars, uppercase, ISO 3166 formatted
   save()
}
```

{% endtab %}

{% tab title="Java" %}

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

{% endtab %}
{% endtabs %}

**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.

{% tabs %}
{% tab title="Kotlin" %}

```kotlin
// This is how you retrieve your custom values. Values are nil by default.
val language: String? = Batch.User.getLanguage(context)
val region: String? = Batch.User.getRegion(context)
```

{% endtab %}

{% tab title="Java" %}

```java
// This is how you retrieve your custom values. Values are nil by default.
String language = Batch.User.getLanguage(context);
String region = Batch.User.getRegion(context);
```

{% endtab %}
{% endtabs %}


---

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