diff --git a/include-fd/stdplus/fd/dupable.hpp b/include-fd/stdplus/fd/dupable.hpp
index 0f810cf..f45575d 100644
--- a/include-fd/stdplus/fd/dupable.hpp
+++ b/include-fd/stdplus/fd/dupable.hpp
@@ -49,6 +49,7 @@
     [[nodiscard]] int release();
 
     int get() const override;
+    explicit operator bool() const noexcept;
 
   private:
     friend class ManagedFd;
diff --git a/include-fd/stdplus/fd/managed.hpp b/include-fd/stdplus/fd/managed.hpp
index a188421..4554785 100644
--- a/include-fd/stdplus/fd/managed.hpp
+++ b/include-fd/stdplus/fd/managed.hpp
@@ -51,6 +51,7 @@
     [[nodiscard]] int release();
 
     int get() const override;
+    explicit operator bool() const noexcept;
 
   private:
     detail::ManagedFdHandle handle;
diff --git a/src/fd/dupable.cpp b/src/fd/dupable.cpp
index d096d04..e9b0982 100644
--- a/src/fd/dupable.cpp
+++ b/src/fd/dupable.cpp
@@ -39,5 +39,10 @@
     return handle.value();
 }
 
+DupableFd::operator bool() const noexcept
+{
+    return static_cast<bool>(handle);
+}
+
 } // namespace fd
 } // namespace stdplus
diff --git a/src/fd/managed.cpp b/src/fd/managed.cpp
index 5669903..b9cfa87 100644
--- a/src/fd/managed.cpp
+++ b/src/fd/managed.cpp
@@ -55,5 +55,10 @@
     return handle.value();
 }
 
+ManagedFd::operator bool() const noexcept
+{
+    return static_cast<bool>(handle);
+}
+
 } // namespace fd
 } // namespace stdplus