ISBLANK
ISBLANK(value)
TRUE when a value is blank: a field nobody has filled in, such as the actual finish of a task that hasn't finished, or the MAX of a list with nothing in it. An error isn't blank, so ISBLANK of a value that failed is FALSE. Empty text, "", is text and not blank either.
Arguments
| Argument | What to give it |
|---|---|
| value | Any single value: a field, or a calculation. |
Examples
Formula=ISBLANK([Actual finish])
TRUE on every task that hasn't finished yet.
Formula=IF(ISBLANK([% complete]), "No progress reported", "")
Flags the tasks with no % complete entered.
Formula on WBS rows=COUNT(FILTER(Tasks, ISBLANK(Tasks[Actual finish])))
On a WBS row: how many tasks under the node are still open.
Reach for something else when
| You want | Use |
|---|---|
| A replacement value for the blanks | COALESCE |
| TRUE when working out a value failed | ISERROR |
| TRUE when a set has no rows, such as no predecessors | ISEMPTY |
Common questions
Why doesn't [Actual finish] = BLANK() find the open tasks?
Comparing anything with a blank gives a blank, never TRUE, so that column is blank on every row. Test for a blank with ISBLANK([Actual finish]).
Is a task with no predecessors blank?
A set is never blank: it has rows or it is empty. Test it with ISEMPTY: ISEMPTY(Predecessors). A value read from an empty set can be blank: ISBLANK(MAX(Predecessors[Finish date])) is TRUE there.