diff --git a/CHANGELOG.md b/CHANGELOG.md
index 44e6498..0c376c8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,15 +2,19 @@
 
 All notable changes to this project will be documented in this file.
 
-### Enum
+## Next Release
 
-- more clang-tidy fix for enum type
+### Enum
 
-## Next Release
+- add operator~ and operator&=
 
 <!-- insertion marker -->
 ## [0.2.4](https://github.com/repo/owner/releases/tag/0.2.4) - 2026-09-16
 
+### Enum
+
+- more clang-tidy fix for enum type
+
 ## [0.2.3](https://github.com/repo/owner/releases/tag/0.2.3) - 2026-08-26
 
 ### Types
diff --git a/include/mstd/enum.hpp b/include/mstd/enum.hpp
index 9c2dbc2..dabceed 100644
--- a/include/mstd/enum.hpp
+++ b/include/mstd/enum.hpp
@@ -134,12 +134,18 @@
             static_cast<Underlying>(lhs) | static_cast<Underlying>(rhs)       \
         );                                                                    \
     }                                                                         \
+                                                                              \
     inline constexpr EnumName& operator|=(EnumName& lhs, EnumName rhs)        \
     {                                                                         \
         lhs = lhs | rhs;                                                      \
         return lhs;                                                           \
     }                                                                         \
                                                                               \
+    inline constexpr EnumName operator~(EnumName value)                       \
+    {                                                                         \
+        return static_cast<EnumName>(~static_cast<Underlying>(value));        \
+    }                                                                         \
+                                                                              \
     struct EnumName##FlagTest                                                 \
     {                                                                         \
         Underlying value;                                                     \
@@ -161,6 +167,12 @@
         )};                                                                   \
     }                                                                         \
                                                                               \
+    inline constexpr EnumName& operator&=(EnumName& lhs, EnumName rhs)        \
+    {                                                                         \
+        lhs = lhs & rhs;                                                      \
+        return lhs;                                                           \
+    }                                                                         \
+                                                                              \
     inline constexpr bool operator!(EnumName lhs)                             \
     {                                                                         \
         return !static_cast<Underlying>(lhs);                                 \