GetTickCount64 function (sysinfoapi.h)

Retrieves the number of milliseconds that have elapsed since the system was started.


ULONGLONG GetTickCount64();

Return value

The number of milliseconds.


The resolution of the GetTickCount64 function is limited to the resolution of the system timer, which is typically in the range of 10 milliseconds to 16 milliseconds. The resolution of the GetTickCount64 function is not affected by adjustments made by the GetSystemTimeAdjustment function.

If you need a higher resolution timer, use a multimedia timer or a high-resolution timer.

To obtain the time the system has spent in the working state since it was started, use the QueryUnbiasedInterruptTime function.

Note  The QueryUnbiasedInterruptTime function produces different results on debug ("checked") builds of Windows, because the interrupt-time count and tick count are advanced by approximately 49 days. This helps to identify bugs that might not occur until the system has been running for a long time. The checked build is available to MSDN subscribers through the Microsoft Developer Network (MSDN) Web site.
To compile an application that uses this function, define _WIN32_WINNT as 0x0600 or later. For more information, see Using the Windows Headers.


Requirement Value
Minimum supported client Windows Vista [desktop apps | UWP apps]
Minimum supported server Windows Server 2008 [desktop apps | UWP apps]
Target Platform Windows
Header sysinfoapi.h (include Windows.h)
Library Kernel32.lib
DLL Kernel32.dll

See also

Time Functions

Windows Time