1. If you use the [#] icon, you can paste your code between the [ CODE ] and [ / CODE ] to make it easier to read
2. Usually there's no need to select a cell
3. I think it's good practice to Dim Variables
4. Assuming that Cells(l, c - 1) contains the string that should be a number, something like this (untested) could work
Function MakeNumber(S As String) As Double
MakeNumber = CDbl(Replace(S, ".", Application.International(xlDecimalSeparator)))
End Function
Sub pressure()
Dim x as Double, y as Double
Do Cells(l, c - 1).Select
x = MakeNUmber (Cells(l, c - 1))
y = Round(x / 14.503, 2)
Selection.NumberFormat = "0.00;;0.00"
Cells(l, c - 1).Value = y
Cells(l, c).Value = "barg"
l = l + 1
Loop While Cells(l, c) = "psig"
End Sub
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