reverse an existing conditional format formula to highlight the opposite data

[Perodin]

I am currently using =COUNTIF($A$4:$A$1088, B3) to conditional highlight B3:AQ1000 for duplicate values found in A4:A1088. How would I make this highlight the reversal, as in all cells that are not duplicates of A4:A1088?
Have already tried =COUNTIF($A$4:$A$1088, "<>"&B3) and more and could use some help.

 

[AlphaFrog]

Try this...

=COUNTIF($A$4:$A$1088, B3)=0
or
=NOT(COUNTIF($A$4:$A$1088, B3))

Or if there are just the two conditions, give all the rows a default "No Duplicate" format and just use the "Duplicate" condition.

 

[Perodin]

Try this...

=COUNTIF($A$4:$A$1088, B3)=0
or
=NOT(COUNTIF($A$4:$A$1088, B3))

Or if there are just the two conditions, give all the rows a default "No Duplicate" format and just use the "Duplicate" condition.

The NOT function got it done, I forgot it even existed. Thank You