How to slugify a string in CodeIgniter?


This page explains how to convert a string to slug in CodeIgniter. Slugifying is the action of converting a string into a valid URL (a slug). For example : le blog à Lulu will become le-blog-a-lulu.

Native solution

CodeIgniter is provided with helpers that can be used to slugify a string.

The following function converts a string into a slug:

$slug = url_title(convert_accented_characters($string), 'dash', true);

However, this functions does not fully support transliteration for foreign languages, especially french. As an example, apostroph, is removed from the string while it should be converted into separator.

Overload url_helper

The best option to fully support transliteration and add futur unsupported characters is to 'extend' the URL helper. Create a new file named MY_url_helper.php in application/helpers/.

Here is the content of the file:

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

// Check if the function does not exists
if ( ! function_exists('slugify'))
    // Slugify a string
    function slugify($string)
        // Get an instance of $this
        $CI =& get_instance(); 


        // Replace unsupported characters (add your owns if necessary)
        $string = str_replace("'", '-', $string);
        $string = str_replace(".", '-', $string);
        $string = str_replace("²", '2', $string);

        // Slugify and return the string
        return url_title(convert_accented_characters($string), 'dash', true);


Use the following code to slugify a string:

$slug = slugify ($string);

See also

Last update : 12/22/2019