Assume you only want this to occur in one column.

Right click on the sheet tab and select view code.
Paste this code in the module:

Private Sub Worksheet_Change(ByVal Target As Range)
On Error GoTo ErrHandler
If Target.Column = 3 Then
If Target.Count 1 Then Exit Sub
If Not IsEmpty(Target.Value) Then
If IsNumeric(Target.Value) Then
sValue = Format(25.4 / Target.Value, "X0000.000;X-0000.000")
Application.EnableEvents = False
Target.Value = sValue
End If
End If
End If
ErrHandler:
Application.EnableEvents = True
End Sub

As written, it reformats any numeric entry in column C. Change the 3 to
reflect the column where you want this behavior (A - 1, B - 2, etc).

--
Regards,
Tom Ogilvy

"Darrell" wrote in message
...
also i would actually prefer to just enter in 15 not
15mm. I don't know if that will make a difference.

Thanks again,
Darrell



-----Original Message-----
If that would work that would be great, however I do not
know anything about event macros.

Darrell


-----Original Message-----
you really can't do that type of math just using a
format.

Also, entering 15mm will make this a string and very
little can be done with
formatting to affect a string.

Do you want an event macro that will make the change?



--
Regards,
Tom Ogilvy


"Darrell" wrote in message
...
I am tring to make a form that I will be able to
enter
in
a number and the formula will do the math. I also
want
it to out put a negitive or positive number.
example:
i
enter in the number 15mm into the cell and it out puts
X0001.693 So this is what I have so far in the
customize
cell featu =25.4/X0000.000;X-0000.000 Can
someone
please help.

Thanks in advanced,

Darrell


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