=DATE(1970,1,1)+A1/86400

This includes a *time*.

39801.25 when formatted is 12/19/2008 6:00 AM

If you want only the date portion:

=INT(DATE(1970,1,1)+A1/86400)

Format as date = 12/19/2008

--
Biff
Microsoft Excel MVP


"mecca" wrote in message
...
I import a date from another program which converts the date from
12/19/2008
to 1,229,666,400. How do I get excel to convert it back?