diff --git a/libcxx/include/__ranges/drop_view.h b/libcxx/include/__ranges/drop_view.h
--- a/libcxx/include/__ranges/drop_view.h
+++ b/libcxx/include/__ranges/drop_view.h
@@ -69,7 +69,7 @@
     drop_view() requires default_initializable<_View> = default;
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr drop_view(_View __base, range_difference_t<_View> __count)
+    constexpr explicit drop_view(_View __base, range_difference_t<_View> __count)
       : __count_(__count)
       , __base_(std::move(__base))
     {
diff --git a/libcxx/include/__ranges/drop_while_view.h b/libcxx/include/__ranges/drop_while_view.h
--- a/libcxx/include/__ranges/drop_while_view.h
+++ b/libcxx/include/__ranges/drop_while_view.h
@@ -51,7 +51,7 @@
     requires default_initializable<_View> && default_initializable<_Pred>
   = default;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr drop_while_view(_View __base, _Pred __pred)
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit drop_while_view(_View __base, _Pred __pred)
       : __base_(std::move(__base)), __pred_(std::in_place, std::move(__pred)) {}
 
   _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
diff --git a/libcxx/include/__ranges/filter_view.h b/libcxx/include/__ranges/filter_view.h
--- a/libcxx/include/__ranges/filter_view.h
+++ b/libcxx/include/__ranges/filter_view.h
@@ -65,10 +65,8 @@
     _LIBCPP_HIDE_FROM_ABI
     filter_view() requires default_initializable<_View> && default_initializable<_Pred> = default;
 
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr filter_view(_View __base, _Pred __pred)
-      : __base_(std::move(__base)), __pred_(in_place, std::move(__pred))
-    { }
+    _LIBCPP_HIDE_FROM_ABI constexpr explicit filter_view(_View __base, _Pred __pred)
+        : __base_(std::move(__base)), __pred_(in_place, std::move(__pred)) {}
 
     template<class _Vp = _View>
     _LIBCPP_HIDE_FROM_ABI
diff --git a/libcxx/include/__ranges/iota_view.h b/libcxx/include/__ranges/iota_view.h
--- a/libcxx/include/__ranges/iota_view.h
+++ b/libcxx/include/__ranges/iota_view.h
@@ -311,7 +311,7 @@
     constexpr explicit iota_view(_Start __value) : __value_(std::move(__value)) { }
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr iota_view(type_identity_t<_Start> __value, type_identity_t<_BoundSentinel> __bound_sentinel)
+    constexpr explicit iota_view(type_identity_t<_Start> __value, type_identity_t<_BoundSentinel> __bound_sentinel)
         : __value_(std::move(__value)), __bound_sentinel_(std::move(__bound_sentinel)) {
       // Validate the precondition if possible.
       if constexpr (totally_ordered_with<_Start, _BoundSentinel>) {
@@ -321,7 +321,7 @@
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr iota_view(__iterator __first, __iterator __last)
+    constexpr explicit iota_view(__iterator __first, __iterator __last)
       requires same_as<_Start, _BoundSentinel>
     : iota_view(std::move(__first.__value_), std::move(__last.__value_)) {}
 
diff --git a/libcxx/include/__ranges/lazy_split_view.h b/libcxx/include/__ranges/lazy_split_view.h
--- a/libcxx/include/__ranges/lazy_split_view.h
+++ b/libcxx/include/__ranges/lazy_split_view.h
@@ -78,14 +78,14 @@
     requires default_initializable<_View> && default_initializable<_Pattern> = default;
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr lazy_split_view(_View __base, _Pattern __pattern)
+  constexpr explicit lazy_split_view(_View __base, _Pattern __pattern)
     : __base_(std::move(__base)), __pattern_(std::move(__pattern)) {}
 
   template <input_range _Range>
     requires constructible_from<_View, views::all_t<_Range>> &&
              constructible_from<_Pattern, single_view<range_value_t<_Range>>>
   _LIBCPP_HIDE_FROM_ABI
-  constexpr lazy_split_view(_Range&& __r, range_value_t<_Range> __e)
+  constexpr explicit lazy_split_view(_Range&& __r, range_value_t<_Range> __e)
     : __base_(views::all(std::forward<_Range>(__r)))
     , __pattern_(views::single(std::move(__e))) {}
 
diff --git a/libcxx/include/__ranges/split_view.h b/libcxx/include/__ranges/split_view.h
--- a/libcxx/include/__ranges/split_view.h
+++ b/libcxx/include/__ranges/split_view.h
@@ -75,13 +75,13 @@
     requires default_initializable<_View> && default_initializable<_Pattern>
   = default;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr split_view(_View __base, _Pattern __pattern)
+  _LIBCPP_HIDE_FROM_ABI explicit constexpr split_view(_View __base, _Pattern __pattern)
       : __base_(std::move(__base)), __pattern_(std::move((__pattern))) {}
 
   template <forward_range _Range>
     requires constructible_from<_View, views::all_t<_Range>> &&
                  constructible_from<_Pattern, single_view<range_value_t<_Range>>>
-  _LIBCPP_HIDE_FROM_ABI constexpr split_view(_Range&& __range, range_value_t<_Range> __elem)
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit split_view(_Range&& __range, range_value_t<_Range> __elem)
       : __base_(views::all(std::forward<_Range>(__range))), __pattern_(views::single(std::move(__elem))) {}
 
   _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
diff --git a/libcxx/include/__ranges/take_view.h b/libcxx/include/__ranges/take_view.h
--- a/libcxx/include/__ranges/take_view.h
+++ b/libcxx/include/__ranges/take_view.h
@@ -64,7 +64,7 @@
   _LIBCPP_HIDE_FROM_ABI
   take_view() requires default_initializable<_View> = default;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr take_view(_View __base, range_difference_t<_View> __count)
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit take_view(_View __base, range_difference_t<_View> __count)
       : __base_(std::move(__base)), __count_(__count) {
     _LIBCPP_ASSERT(__count >= 0, "count has to be greater than or equal to zero");
   }
diff --git a/libcxx/include/__ranges/take_while_view.h b/libcxx/include/__ranges/take_while_view.h
--- a/libcxx/include/__ranges/take_while_view.h
+++ b/libcxx/include/__ranges/take_while_view.h
@@ -67,7 +67,7 @@
     requires default_initializable<_View> && default_initializable<_Pred>
   = default;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr take_while_view(_View __base, _Pred __pred)
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit take_while_view(_View __base, _Pred __pred)
       : __base_(std::move(__base)), __pred_(std::in_place, std::move(__pred)) {}
 
   _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
diff --git a/libcxx/include/__ranges/transform_view.h b/libcxx/include/__ranges/transform_view.h
--- a/libcxx/include/__ranges/transform_view.h
+++ b/libcxx/include/__ranges/transform_view.h
@@ -72,7 +72,7 @@
     requires default_initializable<_View> && default_initializable<_Fn> = default;
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr transform_view(_View __base, _Fn __func)
+  constexpr explicit transform_view(_View __base, _Fn __func)
     : __func_(std::in_place, std::move(__func)), __base_(std::move(__base)) {}
 
   _LIBCPP_HIDE_FROM_ABI