Compter un nombre de caractères dans une cellule

Dim lig As Long

lig = 1

While Range("A" & lig).Value <> ""
     Range("F" & lig).Value = Len(Range("A" & lig).Value)
     lig = lig + 1
Wend

Dim lig As Long
Dim i As Long

lig = Range("A" & Rows.Count).End(xlUp).Row

For i = 1 to lig
     Range("F" & lig).Value = Len(Range("A" & lig).Value)
Next i

Option Explicit

Private Sub Worksheet_SelectionChange(ByVal Target As Range)

    If Target.Column = 1 Then
        Module1.compte
    Else
        Exit Sub
    End If
End Sub

Option Explicit

Sub compte()
Dim lig As Long
Dim i As Long

lig = Range("A" & Rows.Count).End(xlUp).Row

For i = 1 To lig
    If Range("A" & i).Value = "" Then
        Range("F" & i).Value = 0
    Else
        Range("F" & i).Value = Len(Range("A" & i).Value)
    End If
Next i

End Sub

Dim lig As Long
lig = Range("A" & Rows.Count).End(xlUp).Row

For i = 1 To lig

For i = 1 To 26