> ## Documentation Index
> Fetch the complete documentation index at: https://www.integrate.io/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# ETL: NormalizeLanguage

> Normalize a language name or code to an ISO 639 language code in Integrate.io ETL expressions for consistent storage, deduplication, and downstream matching.

## Description

Normalizes a language name or code to an [ISO 639](https://en.wikipedia.org/wiki/ISO_639) language code. Use it to standardize language values from mixed sources before storing, deduplicating, or joining on language.

## Syntax

`NormalizeLanguage(string_expression)`

## Examples

`NormalizeLanguage('English')` returns `'en'`.

`NormalizeLanguage('eng')` returns `'en'`.

`NormalizeLanguage('Français')` returns `'fr'`.

## Return value datatype

String

## Impact of null value

If input is null, returns null. If the input cannot be parsed as a valid language, returns null.