diff --git a/example/CMakeLists.txt b/example/CMakeLists.txt
index 3c2a934..2a30686 100644
--- a/example/CMakeLists.txt
+++ b/example/CMakeLists.txt
@@ -9,8 +9,13 @@ elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
     endif()
 endif()
 
-add_executable(example example.cpp)
-set_target_properties(example PROPERTIES CXX_EXTENSIONS OFF)
-target_compile_features(example PRIVATE cxx_std_17)
-target_compile_options(example PRIVATE ${OPTIONS})
-target_link_libraries(example PRIVATE ${CMAKE_PROJECT_NAME})
+function(make_example target)
+    add_executable(${target} ${target}.cpp)
+    set_target_properties(${target} PROPERTIES CXX_EXTENSIONS OFF)
+    target_compile_features(${target} PRIVATE cxx_std_17)
+    target_compile_options(${target} PRIVATE ${OPTIONS})
+    target_link_libraries(${target} PRIVATE ${CMAKE_PROJECT_NAME})
+endfunction()
+
+make_example(example)
+make_example(enum_flag_example)
diff --git a/example/enum_flag_example.cpp b/example/enum_flag_example.cpp
new file mode 100644
index 0000000..61eefdf
--- /dev/null
+++ b/example/enum_flag_example.cpp
@@ -0,0 +1,100 @@
+// Licensed under the MIT License <http://opensource.org/licenses/MIT>.
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2019 - 2020 Daniil Goncharov <neargye@gmail.com>.
+//
+// Permission is hereby  granted, free of charge, to any  person obtaining a copy
+// of this software and associated  documentation files (the "Software"), to deal
+// in the Software  without restriction, including without  limitation the rights
+// to  use, copy,  modify, merge,  publish, distribute,  sublicense, and/or  sell
+// copies  of  the Software,  and  to  permit persons  to  whom  the Software  is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE  IS PROVIDED "AS  IS", WITHOUT WARRANTY  OF ANY KIND,  EXPRESS OR
+// IMPLIED,  INCLUDING BUT  NOT  LIMITED TO  THE  WARRANTIES OF  MERCHANTABILITY,
+// FITNESS FOR  A PARTICULAR PURPOSE AND  NONINFRINGEMENT. IN NO EVENT  SHALL THE
+// AUTHORS  OR COPYRIGHT  HOLDERS  BE  LIABLE FOR  ANY  CLAIM,  DAMAGES OR  OTHER
+// LIABILITY, WHETHER IN AN ACTION OF  CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE  OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+#include <iostream>
+
+#include <magic_enum.hpp>
+
+enum class AnimalFlags : std::uint64_t { HasClaws = 1 << 1, CanFly = 1 << 2, EatsFish = 1 << 20, Endangered = std::uint64_t{1} << 40 };
+
+int main() {
+  // Enum variable to string name.
+  AnimalFlags f1 = AnimalFlags::CanFly;
+  auto f1_name = magic_enum::flag::enum_name(f1);
+  std::cout << f1_name << std::endl; // CanFly
+
+  // String enum name sequence.
+  constexpr auto names = magic_enum::flag::enum_names<AnimalFlags>();
+  std::cout << "AnimalFlags names:";
+  for (auto n : names) {
+    std::cout << " " << n;
+  }
+  std::cout << std::endl;
+  // AnimalFlags names: HasClaws CanFly EatsFish Endangered
+
+#if 0
+  // String name to enum value.
+  auto f2 = magic_enum::flag::enum_cast<AnimalFlags>("EatsFish");
+  if (f2.has_value() && f2.value() == AnimalFlags::EatsFish) {
+    std::cout << "EatsFish = " << magic_enum::flag::enum_integer(f2.value()) << std::endl; // EatsFish = 4
+  }
+
+  // Integer value to enum value.
+  auto f3 = magic_enum::flag::enum_cast<AnimalFlags>(8);
+  if (f3.has_value() && f3.value() == AnimalFlags::Endangered) {
+    std::cout << "Endangered = " << magic_enum::flag::enum_integer(f3.value()) << std::endl; // Endangered = 8
+  }
+#endif
+
+  // Enum value to integer value.
+  auto f4_integer = magic_enum::flag::enum_integer(AnimalFlags::HasClaws);
+  if (f4_integer == static_cast<std::underlying_type_t<AnimalFlags>>(AnimalFlags::HasClaws)) {
+    std::cout << "HasClaws = " << f4_integer << std::endl; // HasClaws = 2
+  }
+
+  using namespace magic_enum::flag::ostream_operators; // out-of-the-box ostream operator for all enums.
+#if 0
+  // ostream operator for enum.
+  std::cout << f1 << " " << f2 << " " << f3 << std::endl; // CanFly EatsFish Endangered
+#endif
+
+  // Number of enum values.
+  std::cout << "AnimalFlags enum size: " << magic_enum::flag::enum_count<AnimalFlags>() << std::endl; // AnimalFlags enum size: 4
+
+  // Indexed access to enum value.
+  std::cout << "AnimalFlags[0] = " << magic_enum::flag::enum_value<AnimalFlags>(0) << std::endl; // AnimalFlags[0] = HasClaws
+
+  // Enum value sequence.
+  constexpr auto values = magic_enum::flag::enum_values<AnimalFlags>();
+  std::cout << "AnimalFlags values:";
+  for (AnimalFlags f : values) {
+    std::cout << " " << f; // ostream operator for enum.
+  }
+  std::cout << std::endl;
+  // AnimalFlags sequence: HasClaws CanFly EatsFish Endangered
+
+  using namespace magic_enum::flag::bitwise_operators; // out-of-the-box bitwise operators for all enums.
+  // Support operators: ~, |, &, ^, |=, &=, ^=.
+  AnimalFlags flag = AnimalFlags::HasClaws | AnimalFlags::CanFly;
+  std::cout << flag << std::endl; // HasClaws | CanFly
+
+  // Enum pair (value enum, string enum name) sequence.
+  constexpr auto entries = magic_enum::flag::enum_entries<AnimalFlags>();
+  std::cout << "AnimalFlags entries:";
+  for (auto e : entries) {
+    std::cout << " "  << e.second << " = " << magic_enum::flag::enum_integer(e.first);
+  }
+  std::cout << std::endl;
+  // AnimalFlags entries: AnimalFlags entries: HasClaws = 2 CanFly = 4 EatsFish = 1048576 Endangered = 1099511627776
+
+  return 0;
+}
diff --git a/example/example.cpp b/example/example.cpp
index 5e21bf8..d92e87b 100644
--- a/example/example.cpp
+++ b/example/example.cpp
@@ -39,9 +39,9 @@ int main() {
   std::cout << c1_name << std::endl; // RED
 
   // String enum name sequence.
-  constexpr auto color_names = magic_enum::enum_names<Color>();
+  constexpr auto names = magic_enum::enum_names<Color>();
   std::cout << "Color names:";
-  for (auto n : color_names) {
+  for (auto n : names) {
     std::cout << " " << n;
   }
   std::cout << std::endl;
@@ -60,9 +60,9 @@ int main() {
   }
 
   // Enum value to integer value.
-  auto color_integer = magic_enum::enum_integer(c1);
-  if (color_integer == to_integer(Color::RED)) {
-    std::cout << "RED = " << color_integer << std::endl; // RED = -10
+  auto c4_integer = magic_enum::enum_integer(Color::RED);
+  if (c4_integer == static_cast<std::underlying_type_t<Color>>(Color::RED)) {
+    std::cout << "RED = " << c4_integer << std::endl; // RED = -10
   }
 
   using namespace magic_enum::ostream_operators; // out-of-the-box ostream operator for all enums.
@@ -76,9 +76,9 @@ int main() {
   std::cout << "Color[0] = " << magic_enum::enum_value<Color>(0) << std::endl; // Color[0] = RED
 
   // Enum value sequence.
-  constexpr auto colors = magic_enum::enum_values<Color>();
-  std::cout << "Colors sequence:";
-  for (Color c : colors) {
+  constexpr auto values = magic_enum::enum_values<Color>();
+  std::cout << "Colors values:";
+  for (Color c : values) {
     std::cout << " " << c; // ostream operator for enum.
   }
   std::cout << std::endl;
@@ -87,8 +87,8 @@ int main() {
   enum class Flags { A = 1, B = 2, C = 4, D = 8 };
   using namespace magic_enum::bitwise_operators; // out-of-the-box bitwise operators for all enums.
   // Support operators: ~, |, &, ^, |=, &=, ^=.
-  Flags flags = Flags::A | Flags::C;
-  std::cout << flags << std::endl;
+  Flags flag = Flags::A | Flags::C;
+  std::cout << flag << std::endl;
 
   enum color { red, green, blue };
 
@@ -103,9 +103,9 @@ int main() {
   static_assert(magic_enum::is_scoped_enum_v<Flags>);
 
   // Enum pair (value enum, string enum name) sequence.
-  constexpr auto color_entries = magic_enum::enum_entries<Color>();
+  constexpr auto entries = magic_enum::enum_entries<Color>();
   std::cout << "Colors entries:";
-  for (auto e : color_entries) {
+  for (auto e : entries) {
     std::cout << " "  << e.second << " = " << static_cast<int>(e.first);
   }
   std::cout << std::endl;
diff --git a/include/magic_enum.hpp b/include/magic_enum.hpp
index 852d531..81e724f 100644
--- a/include/magic_enum.hpp
+++ b/include/magic_enum.hpp
@@ -277,7 +277,7 @@ constexpr auto reflected_max() noexcept {
   static_assert(is_enum_v<E>, "magic_enum::detail::reflected_max requires enum type.");
 
   if constexpr (IsFlags) {
-    return (std::numeric_limits<std::underlying_type_t<E>>::max)();
+    return (std::numeric_limits<U>::max)();
   } else {
     static_assert(has_max<E>::value, "magic_enum::enum_range requires max.");
     constexpr auto lhs = enum_range<E>::max;
@@ -299,7 +299,7 @@ constexpr auto value(std::size_t i) noexcept {
   static_assert(is_enum_v<E>, "magic_enum::detail::value requires enum type.");
 
   if constexpr (IsFlags) {
-    return static_cast<E>(static_cast<U>(0x1) << static_cast<U>(i));
+    return static_cast<E>(static_cast<U>(1) << static_cast<U>(i));
   } else {
     return static_cast<E>(static_cast<int>(i) + O);
   }
@@ -338,7 +338,7 @@ constexpr auto values() noexcept {
 template <typename E, bool IsFlags = false>
 inline constexpr auto values_v = values<E, IsFlags>();
 
-template <typename T, bool IsFlags = false, typename D = std::decay_t<T>>
+template <typename E, bool IsFlags = false, typename D = std::decay_t<E>>
 using values_t = decltype((values_v<D, IsFlags>));
 
 template <typename E, bool IsFlags = false>
@@ -357,7 +357,7 @@ constexpr std::size_t range_size() noexcept {
   if constexpr (IsFlags) {
     return std::numeric_limits<U>::digits;
   } else {
-    constexpr int range_size = max_v<E> - min_v<E> + 1;
+    constexpr auto range_size = max_v<E> - min_v<E> + 1;
     static_assert(range_size > 0, "magic_enum::enum_range requires valid size.");
     static_assert(range_size < (std::numeric_limits<std::uint16_t>::max)(), "magic_enum::enum_range requires valid size.");
     return static_cast<std::size_t>(range_size);
@@ -365,7 +365,7 @@ constexpr std::size_t range_size() noexcept {
 }
 
 template <typename E, bool IsFlags = false>
-inline constexpr auto range_size_v = range_size<E,IsFlags>();
+inline constexpr auto range_size_v = range_size<E, IsFlags>();
 
 template <typename E>
 using index_t = std::conditional_t<range_size_v<E> < (std::numeric_limits<std::uint8_t>::max)(), std::uint8_t, std::uint16_t>;
@@ -392,22 +392,22 @@ constexpr auto names(std::index_sequence<I...>) noexcept {
 }
 
 template <typename E, bool IsFlags = false>
-inline constexpr auto names_v = names<E, IsFlags>(std::make_index_sequence<count_v<E>>{});
+inline constexpr auto names_v = names<E, IsFlags>(std::make_index_sequence<count_v<E, IsFlags>>{});
 
-template <typename T, bool IsFlags = false, typename D = std::decay_t<T>>
+template <typename E, bool IsFlags = false, typename D = std::decay_t<E>>
 using names_t = decltype((names_v<D, IsFlags>));
 
 template <typename E, bool IsFlags, std::size_t... I>
 constexpr auto entries(std::index_sequence<I...>) noexcept {
   static_assert(is_enum_v<E>, "magic_enum::detail::entries requires enum type.");
 
-  return std::array<std::pair<E, std::string_view>, sizeof...(I)>{{{values_v<E, IsFlags>[I], enum_name_v<E, values_v<E>[I]>}...}};
+  return std::array<std::pair<E, std::string_view>, sizeof...(I)>{{{values_v<E, IsFlags>[I], enum_name_v<E, values_v<E, IsFlags>[I]>}...}};
 }
 
 template <typename E, bool IsFlags = false>
 inline constexpr auto entries_v = entries<E, IsFlags>(std::make_index_sequence<count_v<E, IsFlags>>{});
 
-template <typename T, bool IsFlags = false, typename D = std::decay_t<T>>
+template <typename E, bool IsFlags = false, typename D = std::decay_t<E>>
 using entries_t = decltype((entries_v<D, IsFlags>));
 
 template <typename E, bool IsFlags = false>
@@ -430,26 +430,37 @@ constexpr int undex(U value) noexcept {
   return -1; // Value out of range.
 }
 
-template <typename E>
+template <typename E, typename U = std::underlying_type_t<E>>
 constexpr int endex(E value) noexcept {
   static_assert(is_enum_v<E>, "magic_enum::detail::endex requires enum type.");
 
-  return undex<E>(static_cast<std::underlying_type_t<E>>(value));
+  return undex<E>(static_cast<U>(value));
 }
 
-template <bool, typename T, typename R>
+template <bool, bool, typename T, typename R>
 struct enable_if_enum {};
 
 template <typename T, typename R>
-struct enable_if_enum<true, T, R> {
+struct enable_if_enum<true, false, T, R> {
   using type = R;
   using D = std::decay_t<T>;
   static_assert(supported<D>::value, "magic_enum unsupported compiler (https://github.com/Neargye/magic_enum#compiler-compatibility).");
-  static_assert(count_v<D> > 0, "magic_enum requires enum implementation and valid max and min.");
+  static_assert(count_v<D, false> > 0, "magic_enum requires enum implementation and valid max and min.");
+};
+
+template <typename T, typename R>
+struct enable_if_enum<true, true, T, R> {
+  using type = R;
+  using D = std::decay_t<T>;
+  static_assert(supported<D>::value, "magic_enum unsupported compiler (https://github.com/Neargye/magic_enum#compiler-compatibility).");
+  static_assert(count_v<D, true> > 0, "magic_enum::flag requires enum flag implementation.");
 };
 
 template <typename T, typename R = void>
-using enable_if_enum_t = typename enable_if_enum<std::is_enum_v<std::decay_t<T>>, T, R>::type;
+using enable_if_enum_t = typename enable_if_enum<std::is_enum_v<std::decay_t<T>>, false, T, R>::type;
+
+template <typename T, typename R>
+using enable_if_enum_flags_t = typename enable_if_enum<std::is_enum_v<std::decay_t<T>>, true, T, R>::type;
 
 template <typename T, typename Enable = std::enable_if_t<std::is_enum_v<std::decay_t<T>>>>
 using enum_concept = T;
@@ -532,7 +543,7 @@ template <typename E>
   if constexpr (detail::is_sparse_v<D>) {
     return assert(index < detail::count_v<D>), detail::values_v<D>[index];
   } else {
-    return assert(index < detail::count_v<D>), static_cast<D>(index + detail::min_v<D>);
+    return assert(index < detail::count_v<D>), detail::value<D, false, detail::min_v<D>>(index);
   }
 }
 
@@ -738,9 +749,174 @@ constexpr auto operator^=(E& lhs, E rhs) noexcept -> detail::enable_if_enum_t<E,
 
 } // namespace magic_enum::bitwise_operators
 
-namespace flags {
+namespace flag {
+
+// Returns number of enum flag values.
+template <typename E>
+[[nodiscard]] constexpr auto enum_count() noexcept -> detail::enable_if_enum_flags_t<E, std::size_t> {
+  using D = std::decay_t<E>;
+
+  return detail::count_v<D, true>;
 }
 
+// Returns enum flag value at specified index.
+// No bounds checking is performed: the behavior is undefined if index >= number of enum values.
+template <typename E>
+[[nodiscard]] constexpr auto enum_value(std::size_t index) noexcept -> detail::enable_if_enum_flags_t<E, std::decay_t<E>> {
+  using D = std::decay_t<E>;
+
+  if constexpr (detail::is_sparse_v<D>) {
+    return assert((index < detail::count_v<D, true>)), detail::values_v<D, true>[index];
+  } else {
+    return assert((index < detail::count_v<D, true>)), detail::value<D, true, 0>(index);
+  }
+}
+
+// Obtains value enum flag sequence.
+// Returns std::array with enum flag values, sorted by enum flag value.
+template <typename E>
+[[nodiscard]] constexpr auto enum_values() noexcept -> detail::enable_if_enum_flags_t<E, detail::values_t<E, true>> {
+  using D = std::decay_t<E>;
+
+  return detail::values_v<D, true>;
+}
+
+// Returns string enum flag name from enum value.
+// If enum value does not have name or value out of range, returns empty string.
+template <typename E>
+[[nodiscard]] auto enum_name(E value) -> detail::enable_if_enum_flags_t<E, std::string> {
+  using D = std::decay_t<E>;
+  using U = std::underlying_type_t<D>;
+
+  std::string name;
+  for (std::size_t i = 0; i < detail::count_v<D, true>; ++i) {
+    if (const auto v = enum_value<D>(i); (static_cast<U>(value) & static_cast<U>(v)) != 0) {
+      const auto n = detail::names_v<D, true>[i];
+      if (!name.empty()) {
+        name.append(1, '|');
+      }
+      name.append(n.data(), n.size());
+    }
+  }
+
+  return name;
+}
+
+// Obtains string enum flag name sequence.
+// Returns std::array with string enum flag names, sorted by enum flag value.
+template <typename E>
+[[nodiscard]] constexpr auto enum_names() noexcept -> detail::enable_if_enum_flags_t<E, detail::names_t<E, true>> {
+  using D = std::decay_t<E>;
+
+  return detail::names_v<D, true>;
+}
+
+// Obtains pair (value enum flag, string enum flag name) sequence.
+// Returns std::array with std::pair (value enum flag, string enum flag name), sorted by enum flag value.
+template <typename E>
+[[nodiscard]] constexpr auto enum_entries() noexcept -> detail::enable_if_enum_flags_t<E, detail::entries_t<E, true>> {
+  using D = std::decay_t<E>;
+
+  return detail::entries_v<D, true>;
+}
+
+// TODO: enum_cast
+
+// Obtains enum flag value from integer value.
+// Returns std::optional with enum flag value.
+template <typename E>
+[[nodiscard]] constexpr auto enum_cast(underlying_type_t<E> value) noexcept -> detail::enable_if_enum_flags_t<E, std::optional<std::decay_t<E>>> {
+  using D = std::decay_t<E>;
+  using U = std::underlying_type_t<D>;
+
+  if (value < detail::min_v<D, true> || value > detail::max_v<D, true>) {
+    return std::nullopt; // Out of range.
+  }
+
+  U check_value = U{0};
+  for (std::size_t i = 0; i < detail::count_v<D, true>; ++i) {
+    if (const auto v = enum_value<D>(i); (static_cast<U>(value) & static_cast<U>(v)) != 0) {
+      check_value |= static_cast<U>(v);
+    }
+  }
+
+  if (check_value == value) {
+    return static_cast<D>(value);
+  }
+
+  return std::nullopt; // Invalid value.
+}
+
+// Obtains enum flag value from enum flag string name.
+// Returns std::optional with enum flag value.
+template <typename E, typename BinaryPredicate>
+[[nodiscard]] constexpr auto enum_cast(std::string_view value, BinaryPredicate p) noexcept(std::is_nothrow_invocable_r_v<bool, BinaryPredicate, char, char>) -> detail::enable_if_enum_flags_t<E, std::optional<std::decay_t<E>>> {
+  static_assert(std::is_invocable_r_v<bool, BinaryPredicate, char, char>, "magic_enum::flag::enum_cast requires bool(char, char) invocable predicate.");
+  static_assert(sizeof(E) == 0, "not implemented");
+  return {};
+}
+
+// Obtains enum flag value from enum flag string name.
+// Returns std::optional with enum flag value.
+template <typename E>
+[[nodiscard]] constexpr auto enum_cast(std::string_view value) noexcept -> detail::enable_if_enum_flags_t<E, std::optional<std::decay_t<E>>> {
+  static_assert(sizeof(E) == 0, "not implemented");
+  return {};
+}
+
+// Returns integer value from enum flag value.
+template <typename E>
+[[nodiscard]] constexpr auto enum_integer(E value) noexcept -> detail::enable_if_enum_flags_t<E, underlying_type_t<E>> {
+  return static_cast<underlying_type_t<E>>(value);
+}
+
+// Obtains index in enum flag value sequence from enum flag value.
+// Returns std::optional with index.
+template <typename E>
+[[nodiscard]] constexpr auto enum_index(E value) noexcept -> detail::enable_if_enum_t<E, std::optional<std::size_t>> {
+  static_assert(sizeof(E) == 0, "not implemented");
+  return {};
+}
+
+// Checks whether enum flag contains enumerator with such integer value.
+template <typename E>
+[[nodiscard]] constexpr auto enum_contains(underlying_type_t<E> value) noexcept -> detail::enable_if_enum_flags_t<E, bool> {
+  using D = std::decay_t<E>;
+
+  return enum_cast<D>(value).has_value();
+}
+
+// Checks whether enum flag contains enumerator with such value.
+template <typename E>
+[[nodiscard]] constexpr auto enum_contains(E value) noexcept -> detail::enable_if_enum_flags_t<E, bool> {
+  using D = std::decay_t<E>;
+  using U = std::underlying_type_t<D>;
+
+  return enum_cast<D>(static_cast<U>(value)).has_value();
+}
+
+// Checks whether enum flag contains enumerator with such string enum name.
+template <typename E>
+[[nodiscard]] constexpr auto enum_contains(std::string_view value) noexcept -> detail::enable_if_enum_flags_t<E, bool> {
+  static_assert(sizeof(E) == 0, "not implemented");
+  return {};
+}
+
+namespace ostream_operators {
+
+// TODO: operator<<
+using namespace magic_enum::ostream_operators;
+
+} // namespace magic_enum::flag::ostream_operators
+
+namespace bitwise_operators {
+
+using namespace magic_enum::bitwise_operators;
+
+} // namespace magic_enum::flag::bitwise_operators
+
+} // namespace magic_enum::flag
+
 } // namespace magic_enum
 
 #if defined(__clang__)