Using WordPress ‘format_code_lang()’ PHP function

The format_code_lang() WordPress PHP function is used to return the full name of a language given its two-letter code.


Here’s a basic usage example:

$code = 'fr';
$language = format_code_lang($code);
echo $language; // Outputs: 'French'


  • $code (string – Optional): The two-letter language code. Default is ” (empty string).

More Information

See WordPress Developer Resources: format_code_lang()

This function only works in a multisite environment. It’s not suitable for use in regular plugins on non-multisite installs, as it will result in an Uncaught Error: Call to undefined function format_code_lang() error.


Basic Usage

This code will return the full language name for the code ‘fr’.

$code = 'fr';
$language = format_code_lang($code);
echo $language; // Outputs: 'French'

Default Value

If no parameter is provided, the function will return an empty string.

$language = format_code_lang();
echo $language; // Outputs: ''

Non-Existent Code

For a non-existent or unsupported code, the function will return the code itself.

$code = 'zz';
$language = format_code_lang($code);
echo $language; // Outputs: 'zz'

Case Insensitivity

The function is case-insensitive. It will return the same result for upper and lower case codes.

$code = 'DE';
$language = format_code_lang($code);
echo $language; // Outputs: 'German'

Multisite Environment

Remember, this function only works in a multisite environment.

if (function_exists('format_code_lang')) {
    $code = 'es';
    $language = format_code_lang($code);
    echo $language; // Outputs: 'Spanish'
} else {
    echo 'The function format_code_lang() is not defined in this environment.';