diff --git a/src/corelib/kernel/qsingleshottimer_p.h b/src/corelib/kernel/qsingleshottimer_p.h
index 11354e0b9e5..800936a30de 100644
--- a/src/corelib/kernel/qsingleshottimer_p.h
+++ b/src/corelib/kernel/qsingleshottimer_p.h
@@ -19,9 +19,6 @@
 #include "qabstracteventdispatcher.h"
 #include "qcoreapplication.h"
 #include "qmetaobject_p.h"
-#include "private/qnumeric_p.h"
-
-#include <chrono>
 
 QT_BEGIN_NAMESPACE
 
@@ -43,21 +40,6 @@ public:
 
     void startTimerForReceiver(Duration interval, Qt::TimerType timerType,
                                const QObject *receiver);
-
-    static Duration fromMsecs(std::chrono::milliseconds ms)
-    {
-        using namespace std::chrono;
-        using ratio = std::ratio_divide<std::milli, Duration::period>;
-        static_assert(ratio::den == 1);
-
-        Duration::rep r;
-        if (qMulOverflow<ratio::num>(ms.count(), &r)) {
-            qWarning("QTimer::singleShot(std::chrono::milliseconds, ...): "
-                     "interval argument overflowed when converted to nanoseconds.");
-            return Duration::max();
-        }
-        return Duration{r};
-    }
 Q_SIGNALS:
     void timeout();
 
diff --git a/src/corelib/kernel/qtimer.cpp b/src/corelib/kernel/qtimer.cpp
index 8d3ea7865d6..362285e3694 100644
--- a/src/corelib/kernel/qtimer.cpp
+++ b/src/corelib/kernel/qtimer.cpp
@@ -288,6 +288,23 @@ void QTimer::timerEvent(QTimerEvent *e)
     }
 }
 
+static QAbstractEventDispatcher::Duration from_msecs(std::chrono::milliseconds ms)
+{
+    using Duration = QAbstractEventDispatcher::Duration;
+
+    using namespace std::chrono;
+    using ratio = std::ratio_divide<std::milli, Duration::period>;
+    static_assert(ratio::den == 1);
+
+    Duration::rep r;
+    if (qMulOverflow<ratio::num>(ms.count(), &r)) {
+        qWarning("QTimer::singleShot(std::chrono::milliseconds, ...): "
+                 "interval argument overflowed when converted to nanoseconds.");
+        return Duration::max();
+    }
+    return Duration{r};
+}
+
 /*!
     \internal
 
@@ -332,7 +349,7 @@ void QTimer::singleShotImpl(std::chrono::milliseconds msec, Qt::TimerType timerT
         return;
     }
 
-    new QSingleShotTimer(QSingleShotTimer::fromMsecs(msec), timerType, receiver, slotObj);
+    new QSingleShotTimer(from_msecs(msec), timerType, receiver, slotObj);
 }
 
 /*!
@@ -396,7 +413,7 @@ void QTimer::singleShot(std::chrono::milliseconds msec, Qt::TimerType timerType,
                                       Qt::QueuedConnection);
             return;
         }
-        (void) new QSingleShotTimer(QSingleShotTimer::fromMsecs(msec), timerType, receiver, member);
+        (void) new QSingleShotTimer(from_msecs(msec), timerType, receiver, member);
     }
 }