diff --git a/src/node/interfaces.cpp b/src/node/interfaces.cpp
index f7e2056895..6a3b648e8a 100644
--- a/src/node/interfaces.cpp
+++ b/src/node/interfaces.cpp
@@ -194,7 +194,7 @@ public:
     MasternodeSyncImpl m_masternodeSync;
     CoinJoinOptionsImpl m_coinjoin;
 
-    NodeImpl(NodeContext* context) { setContext(context); }
+    explicit NodeImpl(NodeContext* context) { setContext(context); }
     void initError(const bilingual_str& message) override { InitError(message); }
     bool parseParameters(int argc, const char* const argv[], std::string& error) override
     {
diff --git a/src/qt/test/addressbooktests.h b/src/qt/test/addressbooktests.h
index 5de89c7592..e6d24f202f 100644
--- a/src/qt/test/addressbooktests.h
+++ b/src/qt/test/addressbooktests.h
@@ -15,7 +15,7 @@ class Node;
 class AddressBookTests : public QObject
 {
 public:
-    AddressBookTests(interfaces::Node& node) : m_node(node) {}
+    explicit AddressBookTests(interfaces::Node& node) : m_node(node) {}
     interfaces::Node& m_node;
 
     Q_OBJECT
diff --git a/src/qt/test/rpcnestedtests.h b/src/qt/test/rpcnestedtests.h
index b15c62d25b..2700a48c98 100644
--- a/src/qt/test/rpcnestedtests.h
+++ b/src/qt/test/rpcnestedtests.h
@@ -15,7 +15,7 @@ class Node;
 class RPCNestedTests : public QObject
 {
 public:
-    RPCNestedTests(interfaces::Node& node) : m_node(node) {}
+    explicit RPCNestedTests(interfaces::Node& node) : m_node(node) {}
     interfaces::Node& m_node;
 
     Q_OBJECT
diff --git a/src/qt/test/wallettests.h b/src/qt/test/wallettests.h
index 8ee40bf07f..dfca3370f7 100644
--- a/src/qt/test/wallettests.h
+++ b/src/qt/test/wallettests.h
@@ -15,7 +15,7 @@ class Node;
 class WalletTests : public QObject
 {
  public:
-    WalletTests(interfaces::Node& node) : m_node(node) {}
+    explicit WalletTests(interfaces::Node& node) : m_node(node) {}
     interfaces::Node& m_node;
 
     Q_OBJECT
diff --git a/src/rpc/request.h b/src/rpc/request.h
index b076403936..71fe43a047 100644
--- a/src/rpc/request.h
+++ b/src/rpc/request.h
@@ -38,7 +38,7 @@ public:
     std::string peerAddr;
     const CoreContext& context;
 
-    JSONRPCRequest(const CoreContext& context) : id(NullUniValue), params(NullUniValue), fHelp(false), context(context) {}
+    explicit JSONRPCRequest(const CoreContext& context) : id(NullUniValue), params(NullUniValue), fHelp(false), context(context) {}
 
     //! Initializes request information from another request object and the
     //! given context. The implementation should be updated if any members are
diff --git a/src/script/descriptor.cpp b/src/script/descriptor.cpp
index ef1a7c5b74..ae540d66b5 100644
--- a/src/script/descriptor.cpp
+++ b/src/script/descriptor.cpp
@@ -157,7 +157,7 @@ protected:
     uint32_t m_expr_index;
 
 public:
-    PubkeyProvider(uint32_t exp_index) : m_expr_index(exp_index) {}
+    explicit PubkeyProvider(uint32_t exp_index) : m_expr_index(exp_index) {}
 
     virtual ~PubkeyProvider() = default;
 
diff --git a/src/test/fuzz/signature_checker.cpp b/src/test/fuzz/signature_checker.cpp
index 6c05c7482e..c0cecf53f1 100644
--- a/src/test/fuzz/signature_checker.cpp
+++ b/src/test/fuzz/signature_checker.cpp
@@ -23,7 +23,7 @@ class FuzzedSignatureChecker : public BaseSignatureChecker
     FuzzedDataProvider& m_fuzzed_data_provider;
 
 public:
-    FuzzedSignatureChecker(FuzzedDataProvider& fuzzed_data_provider) : m_fuzzed_data_provider(fuzzed_data_provider)
+    explicit FuzzedSignatureChecker(FuzzedDataProvider& fuzzed_data_provider) : m_fuzzed_data_provider(fuzzed_data_provider)
     {
     }
 
diff --git a/src/test/util/logging.h b/src/test/util/logging.h
index 1fcf7ca305..a49f9a7292 100644
--- a/src/test/util/logging.h
+++ b/src/test/util/logging.h
@@ -32,7 +32,7 @@ class DebugLogHelper
     void check_found();
 
 public:
-    DebugLogHelper(std::string message, MatchFn match = [](const std::string*){ return true; });
+    explicit DebugLogHelper(std::string message, MatchFn match = [](const std::string*){ return true; });
     ~DebugLogHelper() { check_found(); }
 };
 
diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp
index 2b9cb2f976..38b8c5acf2 100644
--- a/src/test/util_tests.cpp
+++ b/src/test/util_tests.cpp
@@ -239,7 +239,7 @@ public:
         std::optional<std::vector<std::string>> list_value;
         const char* error = nullptr;
 
-        Expect(util::SettingsValue s) : setting(std::move(s)) {}
+        explicit Expect(util::SettingsValue s) : setting(std::move(s)) {}
         Expect& DefaultString() { default_string = true; return *this; }
         Expect& DefaultInt() { default_int = true; return *this; }
         Expect& DefaultBool() { default_bool = true; return *this; }
diff --git a/src/tinyformat.h b/src/tinyformat.h
index f75ec7cfca..0211b52600 100644
--- a/src/tinyformat.h
+++ b/src/tinyformat.h
@@ -514,7 +514,7 @@ class FormatArg
         { }
 
         template<typename T>
-        FormatArg(const T& value)
+        explicit FormatArg(const T& value)
             : m_value(static_cast<const void*>(&value)),
             m_formatImpl(&formatImpl<T>),
             m_toIntImpl(&toIntImpl<T>)
@@ -970,7 +970,7 @@ class FormatListN : public FormatList
     public:
 #ifdef TINYFORMAT_USE_VARIADIC_TEMPLATES
         template<typename... Args>
-        FormatListN(const Args&... args)
+        explicit FormatListN(const Args&... args)
             : FormatList(&m_formatterStore[0], N),
             m_formatterStore { FormatArg(args)... }
         { static_assert(sizeof...(args) == N, "Number of args must be N"); }
diff --git a/src/txmempool.h b/src/txmempool.h
index cde068bdcf..8278ab0f4e 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -840,7 +840,7 @@ public:
     class EpochGuard {
         const CTxMemPool& pool;
         public:
-        EpochGuard(const CTxMemPool& in);
+        explicit EpochGuard(const CTxMemPool& in);
         ~EpochGuard();
     };
     // N.B. GetFreshEpoch modifies mutable state via the EpochGuard construction
diff --git a/src/util/hash_type.h b/src/util/hash_type.h
index a3afcd3186..96771546dc 100644
--- a/src/util/hash_type.h
+++ b/src/util/hash_type.h
@@ -13,7 +13,7 @@ protected:
 
 public:
     BaseHash() : m_hash() {}
-    BaseHash(const HashType& in) : m_hash(in) {}
+    explicit BaseHash(const HashType& in) : m_hash(in) {}
 
     unsigned char* begin()
     {
diff --git a/src/validation.cpp b/src/validation.cpp
index add1602cc5..77687552b2 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -566,7 +566,7 @@ private:
     // All the intermediate state that gets passed between the various levels
     // of checking a given transaction.
     struct Workspace {
-        Workspace(const CTransactionRef& ptx) : m_ptx(ptx), m_hash(ptx->GetHash()) {}
+        explicit Workspace(const CTransactionRef& ptx) : m_ptx(ptx), m_hash(ptx->GetHash()) {}
         CTxMemPool::setEntries m_ancestors;
         std::unique_ptr<CTxMemPoolEntry> m_entry;
 
diff --git a/src/wallet/bdb.h b/src/wallet/bdb.h
index f263d40f66..acfaf6686f 100644
--- a/src/wallet/bdb.h
+++ b/src/wallet/bdb.h
@@ -56,7 +56,7 @@ public:
     std::unordered_map<std::string, WalletDatabaseFileId> m_fileids;
     std::condition_variable_any m_db_in_use;
 
-    BerkeleyEnvironment(const fs::path& env_directory);
+    explicit BerkeleyEnvironment(const fs::path& env_directory);
     BerkeleyEnvironment();
     ~BerkeleyEnvironment();
     void Reset();
diff --git a/src/wallet/scriptpubkeyman.h b/src/wallet/scriptpubkeyman.h
index 79cdb1729a..b34689a6b3 100644
--- a/src/wallet/scriptpubkeyman.h
+++ b/src/wallet/scriptpubkeyman.h
@@ -148,7 +148,7 @@ protected:
     WalletStorage& m_storage;
 
 public:
-    ScriptPubKeyMan(WalletStorage& storage) : m_storage(storage) {}
+    explicit ScriptPubKeyMan(WalletStorage& storage) : m_storage(storage) {}
 
     virtual ~ScriptPubKeyMan() {};
     virtual bool GetNewDestination(CTxDestination& dest, std::string& error) { return false; }
@@ -486,7 +486,7 @@ class LegacySigningProvider : public SigningProvider
 private:
     const LegacyScriptPubKeyMan& m_spk_man;
 public:
-    LegacySigningProvider(const LegacyScriptPubKeyMan& spk_man) : m_spk_man(spk_man) {}
+    explicit LegacySigningProvider(const LegacyScriptPubKeyMan& spk_man) : m_spk_man(spk_man) {}
 
     bool GetCScript(const CScriptID &scriptid, CScript& script) const override { return m_spk_man.GetCScript(scriptid, script); }
     bool HaveCScript(const CScriptID &scriptid) const override { return m_spk_man.HaveCScript(scriptid); }
diff --git a/test/lint/extended-lint-cppcheck.sh b/test/lint/extended-lint-cppcheck.sh
index 8c001754e1..67cb45b8fe 100755
--- a/test/lint/extended-lint-cppcheck.sh
+++ b/test/lint/extended-lint-cppcheck.sh
@@ -30,6 +30,7 @@ IGNORED_WARNINGS=(
     "src/protocol.h:.* Class 'CMessageHeader' has a constructor with 1 argument that is not explicit."
     "src/qt/guiutil.h:.* Class 'ItemDelegate' has a constructor with 1 argument that is not explicit."
     "src/rpc/util.h:.* Struct 'RPCResults' has a constructor with 1 argument that is not explicit."
+    "src/rpc/util.h:.* Struct 'UniValueType' has a constructor with 1 argument that is not explicit."
     "src/rpc/util.h:.* style: Struct 'UniValueType' has a constructor with 1 argument that is not explicit."
     "src/script/descriptor.cpp:.* Class 'AddressDescriptor' has a constructor with 1 argument that is not explicit."
     "src/script/descriptor.cpp:.* Class 'ComboDescriptor' has a constructor with 1 argument that is not explicit."
@@ -42,6 +43,11 @@ IGNORED_WARNINGS=(
     "src/script/descriptor.cpp:.* Class 'WSHDescriptor' has a constructor with 1 argument that is not explicit."
     "src/script/script.h:.* Class 'CScript' has a constructor with 1 argument that is not explicit."
     "src/script/standard.h:.* Class 'CScriptID' has a constructor with 1 argument that is not explicit."
+    "src/span.h:.* Class 'Span < const CRPCCommand >' has a constructor with 1 argument that is not explicit."
+    "src/span.h:.* Class 'Span < const char >' has a constructor with 1 argument that is not explicit."
+    "src/span.h:.* Class 'Span < const std :: vector <unsigned char > >' has a constructor with 1 argument that is not explicit."
+    "src/span.h:.* Class 'Span < const uint8_t >' has a constructor with 1 argument that is not explicit."
+    "src/span.h:.* Class 'Span' has a constructor with 1 argument that is not explicit."
     "src/support/allocators/secure.h:.* Struct 'secure_allocator < char >' has a constructor with 1 argument that is not explicit."
     "src/support/allocators/secure.h:.* Struct 'secure_allocator < RNGState >' has a constructor with 1 argument that is not explicit."
     "src/support/allocators/secure.h:.* Struct 'secure_allocator < unsigned char >' has a constructor with 1 argument that is not explicit."
@@ -49,6 +55,9 @@ IGNORED_WARNINGS=(
     "src/test/checkqueue_tests.cpp:.* Struct 'FailingCheck' has a constructor with 1 argument that is not explicit."
     "src/test/checkqueue_tests.cpp:.* Struct 'MemoryCheck' has a constructor with 1 argument that is not explicit."
     "src/test/checkqueue_tests.cpp:.* Struct 'UniqueCheck' has a constructor with 1 argument that is not explicit."
+    "src/test/fuzz/util.h:.* Class 'FuzzedFileProvider' has a constructor with 1 argument that is not explicit."
+    "src/test/fuzz/util.h:.* Class 'FuzzedAutoFileProvider' has a constructor with 1 argument that is not explicit."
+    "src/util/ref.h:.* Class 'Ref' has a constructor with 1 argument that is not explicit."
     "src/wallet/db.h:.* Class 'BerkeleyEnvironment' has a constructor with 1 argument that is not explicit."
 )
 
@@ -66,7 +75,7 @@ function join_array {
 ENABLED_CHECKS_REGEXP=$(join_array "|" "${ENABLED_CHECKS[@]}")
 IGNORED_WARNINGS_REGEXP=$(join_array "|" "${IGNORED_WARNINGS[@]}")
 WARNINGS=$(git ls-files -- "*.cpp" "*.h" ":(exclude)src/dashbls/" ":(exclude)src/leveldb/" ":(exclude)src/secp256k1/" ":(exclude)src/univalue/" | \
-    xargs cppcheck --enable=all -j "$(getconf _NPROCESSORS_ONLN)" --language=c++ --std=c++11 --template=gcc -D__cplusplus -DCLIENT_VERSION_BUILD -DCLIENT_VERSION_IS_RELEASE -DCLIENT_VERSION_MAJOR -DCLIENT_VERSION_MINOR -DCOPYRIGHT_YEAR -DDEBUG -I src/ -q 2>&1 | sort -u | \
+    xargs cppcheck --enable=all -j "$(getconf _NPROCESSORS_ONLN)" --language=c++ --std=c++17 --template=gcc -D__cplusplus -DCLIENT_VERSION_BUILD -DCLIENT_VERSION_IS_RELEASE -DCLIENT_VERSION_MAJOR -DCLIENT_VERSION_MINOR -DCOPYRIGHT_YEAR -DDEBUG -I src/ -q 2>&1 | sort -u | \
     grep -E "${ENABLED_CHECKS_REGEXP}" | \
     grep -vE "${IGNORED_WARNINGS_REGEXP}")
 if [[ ${WARNINGS} != "" ]]; then