diff --git a/include/nlohmann/detail/input/input_adapters.hpp b/include/nlohmann/detail/input/input_adapters.hpp
index d1c7fea11..01bec749b 100644
--- a/include/nlohmann/detail/input/input_adapters.hpp
+++ b/include/nlohmann/detail/input/input_adapters.hpp
@@ -119,7 +119,7 @@ template<typename WideStringType>
 class wide_string_input_adapter : public input_adapter_protocol
 {
   public:
-    wide_string_input_adapter(const WideStringType& w) : str(w) {}
+    explicit wide_string_input_adapter(const WideStringType& w) : str(w) {}
 
     std::char_traits<char>::int_type get_character() noexcept override
     {
diff --git a/include/nlohmann/detail/iterators/json_reverse_iterator.hpp b/include/nlohmann/detail/iterators/json_reverse_iterator.hpp
index 06448191e..11f2a30ac 100644
--- a/include/nlohmann/detail/iterators/json_reverse_iterator.hpp
+++ b/include/nlohmann/detail/iterators/json_reverse_iterator.hpp
@@ -41,11 +41,11 @@ class json_reverse_iterator : public std::reverse_iterator<Base>
     using reference = typename Base::reference;
 
     /// create reverse iterator from iterator
-    json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept
+    explicit json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept
         : base_iterator(it) {}
 
     /// create reverse iterator from base class
-    json_reverse_iterator(const base_iterator& it) noexcept : base_iterator(it) {}
+    explicit json_reverse_iterator(const base_iterator& it) noexcept : base_iterator(it) {}
 
     /// post-increment (it++)
     json_reverse_iterator const operator++(int)
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index 21c37d7db..4c9f4cd90 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -1733,7 +1733,7 @@ template<typename WideStringType>
 class wide_string_input_adapter : public input_adapter_protocol
 {
   public:
-    wide_string_input_adapter(const WideStringType& w) : str(w) {}
+    explicit wide_string_input_adapter(const WideStringType& w) : str(w) {}
 
     std::char_traits<char>::int_type get_character() noexcept override
     {
@@ -4593,7 +4593,7 @@ class primitive_iterator_t
     primitive_iterator_t const operator++(int) noexcept
     {
         auto result = *this;
-        m_it++;
+        ++m_it;
         return result;
     }
 
@@ -4606,7 +4606,7 @@ class primitive_iterator_t
     primitive_iterator_t const operator--(int) noexcept
     {
         auto result = *this;
-        m_it--;
+        --m_it;
         return result;
     }
 
@@ -5433,11 +5433,11 @@ class json_reverse_iterator : public std::reverse_iterator<Base>
     using reference = typename Base::reference;
 
     /// create reverse iterator from iterator
-    json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept
+    explicit json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept
         : base_iterator(it) {}
 
     /// create reverse iterator from base class
-    json_reverse_iterator(const base_iterator& it) noexcept : base_iterator(it) {}
+    explicit json_reverse_iterator(const base_iterator& it) noexcept : base_iterator(it) {}
 
     /// post-increment (it++)
     json_reverse_iterator const operator++(int)