diff --git a/endpoints/data/data.php b/endpoints/data/data.php
index 174e24c2..2376b38c 100644
--- a/endpoints/data/data.php
+++ b/endpoints/data/data.php
@@ -9,7 +9,7 @@ if (!defined('AOWOW_REVISION'))
 class DataBaseResponse extends TextResponse
 {
     protected array $expectedGET = array(
-        'locale'   => ['filter' => FILTER_CALLBACK,     'options' => [Locale::class, 'tryFrom']           ],
+        'locale'   => ['filter' => FILTER_CALLBACK,     'options' => [self::class, 'checkLocale'         ]],
         't'        => ['filter' => FILTER_CALLBACK,     'options' => [self::class, 'checkTextLine'       ]],
         'catg'     => ['filter' => FILTER_VALIDATE_INT                                                    ],
         'skill'    => ['filter' => FILTER_CALLBACK,     'options' => [self::class, 'checkSkill'          ]],
diff --git a/endpoints/guide/edit.php b/endpoints/guide/edit.php
index b2897167..9f7af2b2 100644
--- a/endpoints/guide/edit.php
+++ b/endpoints/guide/edit.php
@@ -45,7 +45,7 @@ class GuideEditResponse extends TemplateResponse
         'description' => ['filter' => FILTER_CALLBACK,     'options' => [self::class, 'checkDescription']                      ],
         'changelog'   => ['filter' => FILTER_CALLBACK,     'options' => [self::class, 'checkTextBlob']                         ],
         'body'        => ['filter' => FILTER_CALLBACK,     'options' => [self::class, 'checkTextBlob']                         ],
-        'locale'      => ['filter' => FILTER_CALLBACK,     'options' => [Locale::class, 'tryFrom']                             ],
+        'locale'      => ['filter' => FILTER_CALLBACK,     'options' => [self::class, 'checkLocale']                           ],
         'category'    => ['filter' => FILTER_VALIDATE_INT, 'options' => ['min_value' =>  1, 'max_value' => 9]                  ],
         'specId'      => ['filter' => FILTER_VALIDATE_INT, 'options' => ['min_value' => -1, 'max_value' => 2,  'default' => -1]],
         'classId'     => ['filter' => FILTER_VALIDATE_INT, 'options' => ['min_value' =>  1, 'max_value' => 11, 'default' =>  0]]
diff --git a/endpoints/locale/locale.php b/endpoints/locale/locale.php
index fccf2962..260ae500 100644
--- a/endpoints/locale/locale.php
+++ b/endpoints/locale/locale.php
@@ -9,7 +9,7 @@ if (!defined('AOWOW_REVISION'))
 class LocaleBaseResponse extends TextResponse
 {
     protected array $expectedGET = array(
-        'locale' => ['filter' => FILTER_CALLBACK, 'options' => [Locale::class, 'tryFrom']]
+        'locale' => ['filter' => FILTER_CALLBACK, 'options' => [self::class, 'checkLocale']]
     );
 
     protected function generate() : void
diff --git a/includes/components/response/baseresponse.class.php b/includes/components/response/baseresponse.class.php
index 986fa509..99d3a8dd 100644
--- a/includes/components/response/baseresponse.class.php
+++ b/includes/components/response/baseresponse.class.php
@@ -645,6 +645,13 @@ abstract class BaseResponse
         return preg_replace('/ +/', ' ', trim($str));
     }
 
+    protected static function checkLocale(string $localeId) : ?Locale
+    {
+        if (Util::checkNumeric($localeId, NUM_CAST_INT))
+            return Locale::tryFrom($localeId);
+        return null;
+    }
+
 
     /********************/
     /* child implements */