Bonjour,
Un exemple dans le fichier joint.
Cdlt.
Sub ReduceStrings()
Dim lastRow As Long, arrData As Variant, i As Long
With ActiveSheet
lastRow = .Cells(.Rows.Count, 5).End(xlUp).Row
arrData = .Cells(2, 5).Resize(lastRow - 1).Value
For i = LBound(arrData) To UBound(arrData)
arrData(i, 1) = VBA.Left(arrData(i, 1), 30)
Next i
With .Cells(2, 5)
.Resize(UBound(arrData)).Value = arrData
.EntireColumn.AutoFit
End With
End With
End Sub