diff --git a/src/corelib/serialization/qjsonvalue.cpp b/src/corelib/serialization/qjsonvalue.cpp
index 481ac64f55f..27cad8941ed 100644
--- a/src/corelib/serialization/qjsonvalue.cpp
+++ b/src/corelib/serialization/qjsonvalue.cpp
@@ -59,6 +59,29 @@
 
 QT_BEGIN_NAMESPACE
 
+static QJsonValue::Type convertFromCborType(QCborValue::Type type) noexcept
+{
+    switch (type) {
+    case QCborValue::Null:
+        return QJsonValue::Null;
+    case QCborValue::True:
+    case QCborValue::False:
+        return QJsonValue::Bool;
+    case QCborValue::Double:
+    case QCborValue::Integer:
+        return QJsonValue::Double;
+    case QCborValue::String:
+        return QJsonValue::String;
+    case QCborValue::Array:
+        return QJsonValue::Array;
+    case QCborValue::Map:
+        return QJsonValue::Object;
+    case QCborValue::Undefined:
+    default:
+        return QJsonValue::Undefined;
+    }
+}
+
 /*!
     \class QJsonValue
     \inmodule QtCore
@@ -608,25 +631,7 @@ QVariant QJsonValue::toVariant() const
  */
 QJsonValue::Type QJsonValue::type() const
 {
-    switch (value.type()) {
-    case QCborValue::Null:
-        return QJsonValue::Null;
-    case QCborValue::True:
-    case QCborValue::False:
-        return QJsonValue::Bool;
-    case QCborValue::Double:
-    case QCborValue::Integer:
-        return QJsonValue::Double;
-    case QCborValue::String:
-        return QJsonValue::String;
-    case QCborValue::Array:
-        return QJsonValue::Array;
-    case QCborValue::Map:
-        return QJsonValue::Object;
-    case QCborValue::Undefined:
-    default:
-        return QJsonValue::Undefined;
-    }
+    return convertFromCborType(value.type());
 }
 
 /*!
@@ -950,6 +955,56 @@ QJsonObject QJsonValueConstRef::toObject() const
     return concrete(*this).toObject();
 }
 
+QJsonValue::Type QJsonValueConstRef::concreteType(QJsonValueConstRef self) noexcept
+{
+    return convertFromCborType(QJsonPrivate::Value::elementHelper(self).type);
+}
+
+bool QJsonValueConstRef::concreteBool(QJsonValueConstRef self, bool defaultValue) noexcept
+{
+    auto &e = QJsonPrivate::Value::elementHelper(self);
+    if (e.type == QCborValue::False)
+        return false;
+    if (e.type == QCborValue::True)
+        return true;
+    return defaultValue;
+}
+
+qint64 QJsonValueConstRef::concreteInt(QJsonValueConstRef self, qint64 defaultValue, bool clamp) noexcept
+{
+    auto &e = QJsonPrivate::Value::elementHelper(self);
+    qint64 v = defaultValue;
+    if (e.type == QCborValue::Double) {
+        // convertDoubleTo modifies the output even on returning false
+        if (!convertDoubleTo<qint64>(e.fpvalue(), &v))
+            v = defaultValue;
+    } else if (e.type == QCborValue::Integer) {
+        v = e.value;
+    }
+    if (clamp && qint64(int(v)) != v)
+        return defaultValue;
+    return v;
+}
+
+double QJsonValueConstRef::concreteDouble(QJsonValueConstRef self, double defaultValue) noexcept
+{
+    auto &e = QJsonPrivate::Value::elementHelper(self);
+    if (e.type == QCborValue::Double)
+        return e.fpvalue();
+    if (e.type == QCborValue::Integer)
+        return e.value;
+    return defaultValue;
+}
+
+QString QJsonValueConstRef::concreteString(QJsonValueConstRef self, const QString &defaultValue)
+{
+    const QCborContainerPrivate *d = QJsonPrivate::Value::container(self);
+    qsizetype index = QJsonPrivate::Value::indexHelper(self);
+    if (d->elements.at(index).type != QCborValue::String)
+        return defaultValue;
+    return d->stringAt(index);
+}
+
 QJsonValue QJsonValueConstRef::concrete(QJsonValueConstRef self) noexcept
 {
     const QCborContainerPrivate *d = QJsonPrivate::Value::container(self);
diff --git a/src/corelib/serialization/qjsonvalue.h b/src/corelib/serialization/qjsonvalue.h
index 11b9ad1b019..4f9c3af5788 100644
--- a/src/corelib/serialization/qjsonvalue.h
+++ b/src/corelib/serialization/qjsonvalue.h
@@ -160,7 +160,7 @@ public:
     inline operator QJsonValue() const { return concrete(*this); }
 
     Q_CORE_EXPORT QVariant toVariant() const;
-    QJsonValue::Type type() const { return concrete(*this).type(); }
+    QJsonValue::Type type() const { return concreteType(*this); }
     bool isNull() const { return type() == QJsonValue::Null; }
     bool isBool() const { return type() == QJsonValue::Bool; }
     bool isDouble() const { return type() == QJsonValue::Double; }
@@ -170,15 +170,15 @@ public:
     bool isUndefined() const { return type() == QJsonValue::Undefined; }
 
     bool toBool(bool defaultValue = false) const
-    { return concrete(*this).toBool(defaultValue); }
+    { return concreteBool(*this, defaultValue); }
     int toInt(int defaultValue = 0) const
-    { return concrete(*this).toInt(defaultValue); }
+    { return concreteInt(*this, defaultValue, true); }
     qint64 toInteger(qint64 defaultValue = 0) const
-    { return concrete(*this).toInteger(defaultValue); }
+    { return concreteInt(*this, defaultValue, false); }
     double toDouble(double defaultValue = 0) const
-    { return concrete(*this).toDouble(defaultValue); }
+    { return concreteDouble(*this, defaultValue); }
     QString toString(const QString &defaultValue = {}) const
-    { return concrete(*this).toString(defaultValue); }
+    { return concreteString(*this, defaultValue); }
     Q_CORE_EXPORT QJsonArray toArray() const;
     Q_CORE_EXPORT QJsonObject toObject() const;
 
@@ -195,6 +195,15 @@ protected:
     QJsonValueConstRef(QJsonObject *object, qsizetype idx)
         : o(object), is_object(true), index(static_cast<quint64>(idx)) {}
 
+    Q_CORE_EXPORT static QJsonValue::Type
+    concreteType(QJsonValueConstRef self) noexcept Q_DECL_PURE_FUNCTION;
+    Q_CORE_EXPORT static bool
+    concreteBool(QJsonValueConstRef self, bool defaultValue) noexcept Q_DECL_PURE_FUNCTION;
+    Q_CORE_EXPORT static qint64
+    concreteInt(QJsonValueConstRef self, qint64 defaultValue, bool clamp) noexcept Q_DECL_PURE_FUNCTION;
+    Q_CORE_EXPORT static double
+    concreteDouble(QJsonValueConstRef self, double defaultValue) noexcept Q_DECL_PURE_FUNCTION;
+    Q_CORE_EXPORT static QString concreteString(QJsonValueConstRef self, const QString &defaultValue);
     Q_CORE_EXPORT static QJsonValue concrete(QJsonValueConstRef self) noexcept;
 
     union {
@@ -228,7 +237,7 @@ public:
     operator QJsonValue() const { return toValue(); }
 
     QVariant toVariant() const;
-    inline QJsonValue::Type type() const { return toValue().type(); }
+    inline QJsonValue::Type type() const { return QJsonValueConstRef::type(); }
     inline bool isNull() const { return type() == QJsonValue::Null; }
     inline bool isBool() const { return type() == QJsonValue::Bool; }
     inline bool isDouble() const { return type() == QJsonValue::Double; }
@@ -237,20 +246,20 @@ public:
     inline bool isObject() const { return type() == QJsonValue::Object; }
     inline bool isUndefined() const { return type() == QJsonValue::Undefined; }
 
-    inline bool toBool(bool defaultValue = false) const { return toValue().toBool(defaultValue); }
-    inline int toInt(int defaultValue = 0) const { return toValue().toInt(defaultValue); }
-    inline qint64 toInteger(qint64 defaultValue = 0) const { return toValue().toInteger(defaultValue); }
-    inline double toDouble(double defaultValue = 0) const { return toValue().toDouble(defaultValue); }
-    inline QString toString(const QString &defaultValue = {}) const { return toValue().toString(defaultValue); }
+    inline bool toBool(bool defaultValue = false) const { return QJsonValueConstRef::toBool(defaultValue); }
+    inline int toInt(int defaultValue = 0) const { return QJsonValueConstRef::toInt(defaultValue); }
+    inline qint64 toInteger(qint64 defaultValue = 0) const { return QJsonValueConstRef::toInteger(defaultValue); }
+    inline double toDouble(double defaultValue = 0) const { return QJsonValueConstRef::toDouble(defaultValue); }
+    inline QString toString(const QString &defaultValue = {}) const { return QJsonValueConstRef::toString(defaultValue); }
     QJsonArray toArray() const;
     QJsonObject toObject() const;
 
-    const QJsonValue operator[](QStringView key) const { return toValue()[key]; }
-    const QJsonValue operator[](QLatin1String key) const { return toValue()[key]; }
-    const QJsonValue operator[](qsizetype i) const { return toValue()[i]; }
+    const QJsonValue operator[](QStringView key) const { return QJsonValueConstRef::operator[](key); }
+    const QJsonValue operator[](QLatin1String key) const { return QJsonValueConstRef::operator[](key); }
+    const QJsonValue operator[](qsizetype i) const { return QJsonValueConstRef::operator[](i); }
 
-    inline bool operator==(const QJsonValue &other) const { return toValue() == other; }
-    inline bool operator!=(const QJsonValue &other) const { return toValue() != other; }
+    inline bool operator==(const QJsonValue &other) const { return QJsonValueConstRef::operator==(other); }
+    inline bool operator!=(const QJsonValue &other) const { return QJsonValueConstRef::operator!=(other); }
 
 private:
     QJsonValue toValue() const;