# Handlebars Helper Function: lowercase

Converts all letters in a string to lowercase.

## Availability

This helper is available in the Winter ’26 release of Marketing Cloud Next.

## Syntax

```handlebars
{{lowercase subject culture}}
```

## Parameters

| Parameter | Type   | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| --------- | ------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `subject` | String | Required. The string to convert to lowercase.                                                                                                                                                                                                                                                                                                                                                                                                                |
| `culture` | String | A POSIX locale code for culture-specific case conversion, such as `tr-TR`. This parameter is helpful with Turkic languages in which the dotless capital letter `I` is converted to a dotless lowercase letter `ı`, as opposed to the lowercase letter `i` found in other Latin alphabets. The operation supports both hyphen (`az-AZ`) and underscore (`az_AZ`) formats. If you don’t specify a culture code, the operation uses the current system culture. |

## Return Value

The operation returns the input string with all characters converted to lowercase.

If the input is null, the operation returns an empty string. If the input isn’t a string, the operation converts it to a string and converts all characters to lowercase.