diff --git a/application/utils.inc.php b/application/utils.inc.php
index 469c9dd22..6b7c4ac35 100644
--- a/application/utils.inc.php
+++ b/application/utils.inc.php
@@ -2819,6 +2819,23 @@ HTML;
 		return $aPrefs[$sShortcutId];
 	}
 
+	//----------------------------------------------
+	// PHP function helpers
+	//----------------------------------------------
+
+	/**
+	 * Helper around the native strlen() PHP method to keep allowing usage of null value when computing the length of a string as null value is no longer allowed with PHP 8.1+
+	 *
+	 * @param string|null $sString
+	 *
+	 * @return int Length of $sString, 0 if null
+	 * @since 3.0.2 N°5172
+	 */
+	public static function StrLen(?string $sString): int
+	{
+		return strlen($sString ?? '');
+	}
+
 	//----------------------------------------------
 	// Environment helpers
 	//----------------------------------------------
diff --git a/test/application/UtilsTest.php b/test/application/UtilsTest.php
index 462ad1eb7..d5ff5ca8f 100644
--- a/test/application/UtilsTest.php
+++ b/test/application/UtilsTest.php
@@ -605,4 +605,26 @@ class UtilsTest extends \Combodo\iTop\Test\UnitTest\ItopTestCase
 			'2G'            => ['2G', 2 * 1024 * 1024 * 1024],
 		];
 	}
+
+	/**
+	 * @param string|null $sString
+	 * @param int $iExpected
+	 *
+	 * @dataProvider StrLenProvider
+	 */
+	public function testStrLen(?string $sString, int $iExpected)
+	{
+		$iComputed = utils::StrLen($sString);
+		self::assertEquals($iExpected, $iComputed, 'Length was not as expected');
+	}
+
+	public function StrLenProvider(): array
+	{
+		return [
+			'null value' => [null, 0],
+			'0 character' => ['', 0],
+			'1 character' => ['a', 1],
+			'5 characters' => ['abcde', 5],
+		];
+	}
 }