diff --git a/boostrap.php b/boostrap.php
index 56b3003..f774d7a 100644
--- a/boostrap.php
+++ b/boostrap.php
@@ -2,6 +2,18 @@
 
 use jrosset\MbstringExtended;
 
+if (!function_exists('mb_ucfirst')) {
+    /**
+     * Multi-bytes implementation for {@see https://www.php.net/manual/function.ucfirst.php ucfirst}
+     *
+     * @param string $string The input string
+     *
+     * @return string The resulting string
+     */
+    function mb_ucfirst (string $string): string {
+        return MbstringExtended::ucfirst($string);
+    }
+}
 if (!function_exists('mb_str_pad')) {
     /**
      * Multi-bytes implementation for {@see https://www.php.net/manual/function.str-pad.php str_pad}
diff --git a/src/MbstringExtended.php b/src/MbstringExtended.php
index c660660..9334225 100644
--- a/src/MbstringExtended.php
+++ b/src/MbstringExtended.php
@@ -6,6 +6,16 @@ namespace jrosset;
  * Class for “missing” mbstring functions
  */
 final class MbstringExtended {
+    /**
+     * Multi-bytes implementation for {@see https://www.php.net/manual/function.ucfirst.php ucfirst}
+     *
+     * @param string $string The input string
+     *
+     * @return string The resulting string
+     */
+    public static function ucfirst (string $string): string {
+        return mb_strtoupper(mb_substr($string, 0, 1)) . mb_strtolower(mb_substr($string, 1));
+    }
     /**
      * Multi-bytes implementation for {@see https://www.php.net/manual/function.str-pad.php str_pad}
      *
diff --git a/tests/test.php b/tests/test.php
index d6a96eb..442f7fc 100644
--- a/tests/test.php
+++ b/tests/test.php
@@ -2,4 +2,7 @@
 
 require_once __DIR__ . '/../vendor/autoload.php';
 
-echo mb_str_pad('𝄞', 20, '=', STR_PAD_RIGHT, 'UTF-8');
+var_dump(
+    mb_ucfirst('TEST AVEC Plusieurs mOts'),
+    mb_str_pad('𝄞', 20, '=', STR_PAD_RIGHT, 'UTF-8')
+);