Nested if with today function and datedif function

I need help please.

I have a estimated date and and actual date. The objective is to see how many days difference is there between my Estimated Date (R8) and my Actual date (S8), however sometimes there is no date in the Actual date (S8)

R8 has the first date in it and S8 has the Actual date in it - sometimes the actual date occurs borfore the estimated date, the problem I am getting is that it renturns #Num when this occurs. (Somtimes is doesn't have a date and the cell is empty, hence my S8="")

I would like it to have a 0 if this occurs. If I didn't have the today portion first then I wouldn't have a problem, but I just can't work out where to put the iserror function to solve this.

This is the formulas so far and it works great except when the date occurs before the date in R8

=IF(S8="",TODAY()-R8,DATEDIF(R8,S8,"D"))

Your help would be very much appreciated.

Try this ...

=IF(S8="",TODAY(),S8)-R8

I have attached a sample.

Thank you - can you explain the formula to me please.

Try

=IF(AND(H2<>"",G2=H2),"On Order",IF(H2="",TODAY(),H2)-G2)

Thanks you so so much, that worked very well.