diff --git a/Source/Core/Common/Timer.cpp b/Source/Core/Common/Timer.cpp
index 81fb792ff3..d33d1951eb 100644
--- a/Source/Core/Common/Timer.cpp
+++ b/Source/Core/Common/Timer.cpp
@@ -254,7 +254,7 @@ std::string Timer::GetDateTimeFormatted(double time)
 
 #ifdef _WIN32
   wchar_t tmp[32] = {};
-  wcsftime(tmp, sizeof(tmp), L"%x %X", localTime);
+  wcsftime(tmp, std::size(tmp), L"%x %X", localTime);
   return WStringToUTF8(tmp);
 #else
   char tmp[32] = {};
diff --git a/Source/Core/Core/HW/EXI/BBA/TAP_Win32.cpp b/Source/Core/Core/HW/EXI/BBA/TAP_Win32.cpp
index a421484005..75b9edb5ea 100644
--- a/Source/Core/Core/HW/EXI/BBA/TAP_Win32.cpp
+++ b/Source/Core/Core/HW/EXI/BBA/TAP_Win32.cpp
@@ -35,7 +35,7 @@ bool IsTAPDevice(const TCHAR* guid)
     TCHAR net_cfg_instance_id[256];
     DWORD data_type;
 
-    len = sizeof(enum_name);
+    len = _countof(enum_name);
     status = RegEnumKeyEx(netcard_key, i, enum_name, &len, nullptr, nullptr, nullptr, nullptr);
 
     if (status == ERROR_NO_MORE_ITEMS)
@@ -43,7 +43,8 @@ bool IsTAPDevice(const TCHAR* guid)
     else if (status != ERROR_SUCCESS)
       return false;
 
-    _sntprintf(unit_string, sizeof(unit_string), _T("%s\\%s"), ADAPTER_KEY, enum_name);
+    _sntprintf(unit_string, _countof(unit_string), _T("%s\\%s"), ADAPTER_KEY, enum_name);
+    unit_string[_countof(unit_string) - 1] = _T('\0');
 
     status = RegOpenKeyEx(HKEY_LOCAL_MACHINE, unit_string, 0, KEY_READ, &unit_key);
 
@@ -110,14 +111,15 @@ bool GetGUIDs(std::vector<std::basic_string<TCHAR>>& guids)
     DWORD name_type;
     const TCHAR name_string[] = _T("Name");
 
-    len = sizeof(enum_name);
+    len = _countof(enum_name);
     status = RegEnumKeyEx(control_net_key, i, enum_name, &len, nullptr, nullptr, nullptr, nullptr);
 
     if (status != ERROR_SUCCESS)
       continue;
 
-    _sntprintf(connection_string, sizeof(connection_string), _T("%s\\%s\\Connection"),
+    _sntprintf(connection_string, _countof(connection_string), _T("%s\\%s\\Connection"),
                NETWORK_CONNECTIONS_KEY, enum_name);
+    connection_string[_countof(connection_string) - 1] = _T('\0');
 
     status = RegOpenKeyEx(HKEY_LOCAL_MACHINE, connection_string, 0, KEY_READ, &connection_key);