How do I create a formula to return a blank cell if false?

Hi there

I have been trying to create an IF statement that returns a blank cell if there is no date in A1. It does the calculation if I use the following formula =DATEDIF(A16,TODAY(),"D")/7 however if I fill down with this formula the rows that have no dates in them become 5626 days. I want it to be left blank if the date has not yet been entered. I usually put ,"") at the end but have tried all variations and nothing seems to work.

I would be very grateful if somebody could help.

Many thanks
Vivecat

I've put in the formula but is returning with VALUE?? I've attached the file as I have validations in these cells as well and it may be why it is not working. I am trying to fully automate the worksheet for others who do not have any excel knowledge to use.

Apart from this previous formula not working I also want the row to hide once the file has been closed if a name is typed into the allocation column. I have. I think, filtered it on only showing blanks but when I close it and reopen the row it is still there.

Do you know what I maybe doing wrong.

many thanks
Vivecat

Noob's formula works fine; maybe you put it in the wrong row.

Also, you don't need the DATEDIF function to find the difference in days; just subtract. Put this formula in F2 and copy down:

=IF(A2="", "", (TODAY() - A2) / 7 )

Your right. I must have done something wrong.

Many thanks to both of you for your help on this.

kind regards
Vivecat