Speeding up deleting of columns in Excel - excel

Question

I'm using this formula to delete empty columns in my sheet. But it takes around 15-20min to delete them. Can I somehow speed up this proces? It's weird that it takes so long and I'm only working with 100 columns.
For j = 1 To 5
For i = 40 To 146
If Sheet8.cells(4, i) = "" Then
Columns(i).EntireColumn.Delete
End If
Next i
Next j

Answer 1

If you have real bank cells use #Patrick Honorez answer using SpecialCells(xlCellTypeBlanks) which is faster.
But if you have no real blank cells (eg formulas that show as "") then you can use this:
Dim DeleteRange As Range
With sheet8
Dim i As Long
For i = 40 To 146
If .Cells(4, i).Value = vbNullString Then 'vbNullString = ""
If DeleteRange Is Nothing Then
Set DeleteRange = .Columns(i)
Else
Set DeleteRange = Union(DeleteRange, .Columns(i))
End If
End If
Next i
End With
If Not DeleteRange Is Nothing Then 'check if there is something to delete
DeleteRange.EntireColumn.Delete
End If
It collects all columns that you want to delete in DeleteRange and then deletes them at once. This is faster than deleting each column on its own, because each delete action needs its time (and here we have only one delete action).
Note that we don't need to loop backwards here because we only collect the columns within the loop but delete action comes after the loop, so it doesn't affect the loop counting at all.

Answer 2

Try:
For i = 146 To 40 step -1
If Sheet8.cells(4, i) = "" Then
Columns(i).EntireColumn.Delete
End If
Next i

Answer 3

Try adjusting this for your needs. I think nothing can go faster :-)
Sub test()
Range("C3:j17").SpecialCells(xlCellTypeBlanks).EntireColumn.Delete
End Sub

Answer 4

I would suggest to do it like that.
Option Explicit
Private Sub TurnOffFunctionality()
Application.Calculation = xlCalculationManual
Application.DisplayStatusBar = False
Application.EnableEvents = False
Application.ScreenUpdating = False
End Sub
Private Sub TurnOnFunctionality()
Application.Calculation = xlCalculationAutomatic
Application.DisplayStatusBar = True
Application.EnableEvents = True
Application.ScreenUpdating = True
End Sub
Sub TestIt()
Dim i As Long
TurnOffFunctionality
For i = 146 To 40 Step -1
If Sheet8.Cells(4, i) = "" Then
Columns(i).EntireColumn.Delete
End If
Next i
TurnOnFunctionality
End Sub
Turning off especially re-calculation will make sure that a re-caculation is not triggered with every deletion of a single column in the loop. This could probably be the cause of the long run time.