If the input data are formatted so that Excel recognises them as times, then
it doesn't matter whether they are 12 hour or 24 hour format. If you want
to change them all to one format, use Format/ Cells/ Number/ Time, and
choose to suit your preference.
You may have problems if your data are treated as text because they have
spare spaces or non-breaking spaces. In that case you'd have to change them
to real times before formatting them.
--
David Biddulph

"Enda K" <Enda wrote in message
...
I am using Excel. I have a mix of 24hr and 12hr AM/PM format pulling from a
database. I want to reformat all dates with time to the 24hr clock so that
I
can then have 1 format to manipulate