the results can be entered into a comment
31.496X15.748X11.811

Just a technique for display might be to use the Multiplication symbol
instead of the letter X.

Sub Demo()
Dim j As Long
Dim v As Variant

With ActiveCell
'// Remove...
.Value = "800X400X300"

v = Split(Trim(.Value), "X")

For j = LBound(v) To UBound(v)
v(j) = Format(v(j) / 25.4, "#.000")
Next j

.ClearComments
.AddComment Join(v, Space(1) & Chr(215) & Space(1))
.Comment.Shape.TextFrame.AutoSize = True
End With
End Sub

--
HTH
Dana DeLouis

"rpick60" wrote in message
...
How would I convert a number from MM to Inch and add the results to
the comment?
here is what is the cell
800X400X300
the results can be entered in to a comment
31.496X15.748X11.811
or
31.496
15.748
11.811

the formula is 800/25.4= 31.496

Thanks in advanced