diff --git a/CHANGELOG.md b/CHANGELOG.md
index f32ca33c..9b20e84c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -26,6 +26,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
   - executed commands are not displayed on the system default language and encoding (requires Flatpak >= 1.12) [#242](https://github.com/vinifmor/bauh/issues/242)
   - applications and runtimes descriptions are not displayed on the system default language (when available) [#242](https://github.com/vinifmor/bauh/issues/242)
 
+- Web
+  - using the wrong locale format for the Accept-Language header
+
 - UI:
   - fix: rare crash when updating table items
 
diff --git a/bauh/gems/web/controller.py b/bauh/gems/web/controller.py
index 615359a6..629b9916 100644
--- a/bauh/gems/web/controller.py
+++ b/bauh/gems/web/controller.py
@@ -59,6 +59,8 @@ RE_PROTOCOL_STRIP = re.compile(r'[a-zA-Z]+://')
 RE_SEVERAL_SPACES = re.compile(r'\s+')
 RE_SYMBOLS_SPLIT = re.compile(r'[\-|_\s:.]')
 
+DEFAULT_LANGUAGE_HEADER = 'en-US, en'
+
 
 class WebApplicationManager(SoftwareManager):
 
@@ -77,12 +79,28 @@ class WebApplicationManager(SoftwareManager):
         self.idxman = SearchIndexManager(logger=context.logger)
         self._custom_actions: Optional[Iterable[CustomSoftwareAction]] = None
 
-    def _get_lang_header(self) -> str:
+    def get_accept_language_header(self) -> str:
         try:
-            system_locale = locale.getdefaultlocale()
-            return system_locale[0] if system_locale else 'en_US'
+            syslocale = locale.getdefaultlocale()
+
+            if syslocale:
+                locale_split = syslocale[0].split('_')
+
+                if len(locale_split) == 2:
+                    sys_lang = f'{locale_split[0]}-{locale_split[1]}, {locale_split[0]}'
+
+                    if DEFAULT_LANGUAGE_HEADER.split(',')[1].strip() not in sys_lang:
+                        return f'{sys_lang}, {DEFAULT_LANGUAGE_HEADER}'
+
+                    return sys_lang
+
+                else:
+                    return f'{syslocale[0]}, {DEFAULT_LANGUAGE_HEADER}'
+            else:
+                return DEFAULT_LANGUAGE_HEADER
+
         except:
-            return 'en_US'
+            return DEFAULT_LANGUAGE_HEADER
 
     def clean_environment(self, root_password: Optional[str], watcher: ProcessWatcher) -> bool:
         handler = ProcessHandler(watcher)
@@ -221,7 +239,7 @@ class WebApplicationManager(SoftwareManager):
         super(WebApplicationManager, self).serialize_to_disk(pkg=pkg, icon_bytes=None, only_icon=False)
 
     def _request_url(self, url: str) -> Optional[Response]:
-        headers = {'Accept-language': self._get_lang_header(), 'User-Agent': UA_CHROME}
+        headers = {'Accept-language': self.get_accept_language_header(), 'User-Agent': UA_CHROME}
 
         try:
             return self.http_client.get(url, headers=headers, ignore_ssl=True, single_call=True, session=False, allow_redirects=True)
diff --git a/tests/gems/web/__init__.py b/tests/gems/web/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/gems/web/test_controller.py b/tests/gems/web/test_controller.py
new file mode 100644
index 00000000..442ffe24
--- /dev/null
+++ b/tests/gems/web/test_controller.py
@@ -0,0 +1,47 @@
+from unittest import TestCase
+from unittest.mock import Mock, patch
+
+from bauh.gems.web.controller import DEFAULT_LANGUAGE_HEADER
+from bauh.gems.web.controller import WebApplicationManager
+
+
+class ControllerTest(TestCase):
+
+    def test_DEFAULT_LANGUAGE_HEADER(self):
+        self.assertEqual('en-US, en', DEFAULT_LANGUAGE_HEADER)
+
+
+class WebApplicationManagerTest(TestCase):
+
+    def setUp(self):
+        self.manager = WebApplicationManager(context=Mock())
+
+    @patch('locale.getdefaultlocale', side_effect=Exception)
+    def test_get_accept_language_header__must_return_default_locale_when_exception_raised(self, getdefaultlocale: Mock):
+        returned = self.manager.get_accept_language_header()
+        self.assertEqual(DEFAULT_LANGUAGE_HEADER, returned)
+        getdefaultlocale.assert_called_once()
+
+    @patch('locale.getdefaultlocale', return_value=None)
+    def test_get_accept_language_header__must_return_default_locale_when_no_locale_is_returned(self, getdefaultlocale: Mock):
+        returned = self.manager.get_accept_language_header()
+        self.assertEqual(DEFAULT_LANGUAGE_HEADER, returned)
+        getdefaultlocale.assert_called_once()
+
+    @patch('locale.getdefaultlocale', return_value=['es_AR'])
+    def test_get_accept_language_header__must_return_the_system_locale_without_underscore_plus_default_locale(self, getdefaultlocale: Mock):
+        returned = self.manager.get_accept_language_header()
+        self.assertEqual(f'es-AR, es, {DEFAULT_LANGUAGE_HEADER}', returned)
+        getdefaultlocale.assert_called_once()
+
+    @patch('locale.getdefaultlocale', return_value=['es'])
+    def test_get_accept_language_header__must_return_the_simple_system_locale_plus_default_locale(self, getdefaultlocale: Mock):
+        returned = self.manager.get_accept_language_header()
+        self.assertEqual(f'es, {DEFAULT_LANGUAGE_HEADER}', returned)
+        getdefaultlocale.assert_called_once()
+
+    @patch('locale.getdefaultlocale', return_value=['en_IN'])
+    def test_get_accept_language_header__must_not_concatenate_default_locale_if_system_locale_has_it(self, getdefaultlocale: Mock):
+        returned = self.manager.get_accept_language_header()
+        self.assertEqual(f'en-IN, en', returned)
+        getdefaultlocale.assert_called_once()