# Date calculations to determine "yesterday"

Hi all - I know dates and timezones are complex, and I’ve tried to do my homework but I’m really stumped. My end goal is to identify records created yesterday and send off a notification. To start, I’m attempting to calculate how many days are between Created Date (w/o time) and Today (without time). Ideally, I would say if Today - Created Date = 1, then that record was created yesterday and I can filter on those records in a view.

Trial 1:

• ‘Created Date’ is set to use GMT for all collaborators, and does not include time
• I created a formula variable called ‘Today’ with formula “TODAY()”, which is set to use GMT for all collaborators and does not include time. The value shows as 8/31/22.
• In a formula field I compared the 2 dates: DATETIME_DIFF(Today,{Created Date},‘days’)
• For both yesterday and today, the value of that comparison was zero
• with Detail: today is 8/31/22. The record created yesterday on 8/30/22 had a calculated value of 0. The record created today on 8/31/22 had a calculated value of 0.

Trial 2: (w/o GMT)

• ‘Created Date’ does not use GMT and displays with EDT
• The ‘Today’ variable that uses TODAY() does not use GMT and displays with EDT. But the value of Today now shows as 8/30/22 (which is not Today in EDT)
• On the same DATETIME_DIFF formula above, both records created yesterday and today show 0.

Any help would be appreciated.

Hi Sharon, yeah, I feel like using `DATETIME_DIFF` might not be the way to go here. Don’t get me wrong, totally doable, but thinking about all the edge cases around that made my head hurt

If I were you, I think I would use a formula to check whether the created date matched yesterday’s date instead, and I’ve attached the formula below

``````IF(
=
DATETIME_PARSE(
DATETIME_FORMAT(
Created,
'DD MM YYYY'
),
'DD MM YYYY'
),
"Yesterday"
)
``````

And here’s a link to the base

The base has the `Today` field set up as a date field purely so that we can see the formula at work

1 Like

The `IS_SAME` function lets you compare if two dates are the same date, up to any unit that you specify.

So, if you keep both of your fields as GMT, then your formula could look like this:

``````IS_SAME(
{Created Date},
'days')
``````