How do you test running time of VBA code?

Unless your functions are very slow, you're going to need a very high-resolution timer. The most accurate one I know is QueryPerformanceCounter. Google it for more info. Try pushing the following into a class, call it CTimer say, then you can make an instance somewhere global and just call .StartCounter and .TimeElapsed

Option ExplicitPrivate Type LARGE_INTEGER    lowpart As Long    highpart As LongEnd TypePrivate Declare Function QueryPerformanceCounter Lib "kernel32" (lpPerformanceCount As LARGE_INTEGER) As LongPrivate Declare Function QueryPerformanceFrequency Lib "kernel32" (lpFrequency As LARGE_INTEGER) As LongPrivate m_CounterStart As LARGE_INTEGERPrivate m_CounterEnd As LARGE_INTEGERPrivate m_crFrequency As DoublePrivate Const TWO_32 = 4294967296# ' = 256# * 256# * 256# * 256#Private Function LI2Double(LI As LARGE_INTEGER) As DoubleDim Low As Double    Low = LI.lowpart    If Low < 0 Then        Low = Low + TWO_32    End If    LI2Double = LI.highpart * TWO_32 + LowEnd FunctionPrivate Sub Class_Initialize()Dim PerfFrequency As LARGE_INTEGER    QueryPerformanceFrequency PerfFrequency    m_crFrequency = LI2Double(PerfFrequency)End SubPublic Sub StartCounter()    QueryPerformanceCounter m_CounterStartEnd SubProperty Get TimeElapsed() As DoubleDim crStart As DoubleDim crStop As Double    QueryPerformanceCounter m_CounterEnd    crStart = LI2Double(m_CounterStart)    crStop = LI2Double(m_CounterEnd)    TimeElapsed = 1000# * (crStop - crStart) / m_crFrequencyEnd Property

The Timer function in VBA gives you the number of seconds elapsed since midnight, to 1/100 of a second.

Dim t as singlet = Timer'codeMsgBox Timer - t

If you are trying to return the time like a stopwatch you could use thefollowing API which returns the time in milliseconds since system startup:

Public Declare Function GetTickCount Lib "kernel32.dll" () As LongSub testTimer()Dim t As Longt = GetTickCountFor i = 1 To 1000000a = a + 1NextMsgBox GetTickCount - t, , "Milliseconds"End Sub

after http://www.pcreview.co.uk/forums/grab-time-milliseconds-included-vba-t994765.html (as timeGetTime in winmm.dll was not working for me and QueryPerformanceCounter was too complicated for the task needed)