Duration formula

Hi there,

I have tried reaching out to Smartsheet for help and received nothing so hopping on here as a desperate last attempt.

I have a column with a start date and another column with a finish date. I am trying to get the following column to calculate the days between the start and finish dates. Can someone please give me a formula to do this?

I have tried


and the formula lights up like it is working but then will say #invalid and I don't understand.


  • Lucas Rayala
    Lucas Rayala ✭✭✭✭✭✭
    edited 03/10/22

    Possible issue: if the start and finish date columns are not checked as DATE in their properties, then you would get an invalid error. To check, right click the column header, select Edit Column Properties, then select Date.

    If this is a big sheet and you are populating large columns, consider using the @row instead:


    After you've tabbed out of the cell (and you've checked the formula is working appropriately), right click the cell with the formula and select "Make Column Formula". Column formulas only work with @row entries--you can not reference specific rows as your original formula does.

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