"Sandy Mann" wrote in message
...

Thanks for sharing that Bruno,

It also returns 24:00 if both cells are blank, if that is a problem then
you could add another test:

=A2-A1+(A2<=A1)*(A1<"")

Or
=(A2-A1+(A2<=A1))*AND(A1<"",A2<"")

Ciao
Bruno