Function to convert column number to letter?

Question

Does anyone have an Excel VBA function which can return the column letter(s) from a number?

For example, entering 100 should return CV.

Answer 1

Furthering on brettdj answer, here is to make the input of column number optional. If the column number input is omitted, the function returns the column letter of the cell that calls to the function. I know this can also be achieved using merely ColumnLetter(COLUMN()), but i thought it'd be nice if it can cleverly understand so.

Public Function ColumnLetter(Optional ColumnNumber As Long = 0) As String
    If ColumnNumber = 0 Then
        ColumnLetter = Split(Application.Caller.Address(True, False, xlA1), "$")(0)
    Else
        ColumnLetter = Split(Cells(1, ColumnNumber).Address(True, False, xlA1), "$")(0)
    End If
End Function

The trade off of this function is that it would be very very slightly slower than brettdj's answer because of the IF test. But this could be felt if the function is repeatedly used for very large amount of times.

Answer 2

Cap A is 65 so:

MsgBox Chr(ActiveCell.Column + 64)

Found in: http://www.vbaexpress.com/forum/showthread.php?6103-Solved-get-column-letter

Answer 3

Here is a simple one liner that can be used.

ColumnLetter = Mid(Cells(Row, LastColA).Address, 2, 1)

It will only work for a 1 letter column designation, but it is nice for simple cases. If you need it to work for exclusively 2 letter designations, then you could use the following:

ColumnLetter = Mid(Cells(Row, LastColA).Address, 2, 2)

Answer 4

Sub GiveAddress()
    Dim Chara As String
    Chara = ""
    Dim Num As Integer
    Dim ColNum As Long
    ColNum = InputBox("Input the column number")

    Do
        If ColNum < 27 Then
            Chara = Chr(ColNum + 64) & Chara
            Exit Do
        Else
            Num = ColNum / 26
            If (Num * 26) > ColNum Then Num = Num - 1
            If (Num * 26) = ColNum Then Num = ((ColNum - 1) / 26) - 1
            Chara = Chr((ColNum - (26 * Num)) + 64) & Chara
            ColNum = Num
        End If
    Loop

    MsgBox "Address is '" & Chara & "'."
End Sub

Answer 5

Column letter from column number can be extracted using formula by following steps
1. Calculate the column address using ADDRESS formula
2. Extract the column letter using MID and FIND function

Example:
1. ADDRESS(1000,1000,1)
results $ALL$1000
2. =MID(F15,2,FIND("$",F15,2)-2)
results ALL asuming F15 contains result of step 1

In one go we can write
MID(ADDRESS(1000,1000,1),2,FIND("$",ADDRESS(1000,1000,1),2)-2)

Answer 6

This is a version of robartsd's answer (with the flavor of Jan Wijninckx's one line solution), using recursion instead of a loop.

Public Function ColumnLetter(Column As Integer) As String
    If Column < 1 Then Exit Function
    ColumnLetter = ColumnLetter(Int((Column - 1) / 26)) & Chr(((Column - 1) Mod 26) + Asc("A"))
End Function

I've tested this with the following inputs:

1   => "A"
26  => "Z"
27  => "AA"
51  => "AY"
702 => "ZZ"
703 => "AAA" 
-1  => ""
-234=> ""