Number of days in certain month | Days left in month

Hi James!

That’s a fun question. Airtable’s formulas are a little different than Excel, but you can acheive the same results. Here’s how I went about it:

1. find the first day of the month by finding the year and month, adding “01” for the day, and parsing them together:

DATETIME_PARSE(DATETIME_FORMAT(Date,'YYYY') & DATETIME_FORMAT(Date,'MM') & '01','YYYYMMDD')

2. Find the last day of the month by adding one month to the first day of the month and then subtracting one day:

DATEADD(DATEADD({First Day of Month},1,'month'),-1,'day')

3. Find the number of days in the month by finding what number day the last day is:

DATETIME_FORMAT({Last Day of Month},'D')

4. Find the days left by finding the number of the current day and subtracting it from the number of days in the month:

{Days In Month} - DATETIME_FORMAT(Date,'D')

Here’s the base where I made these formulas: https://airtable.com/invite/l?inviteId=invAGgFDa1m3xz4Ix&inviteToken=1941c133a29e2c9439cc26d23ed92df97fe2548c5384157fce529a914613e88f

And a very useful overview of date formatting in Airtable: https://support.airtable.com/hc/en-us/articles/216141218-Supported-format-specifiers-for-DATETIME-FORMAT

[SOLVED]
That’s amazing, Julian. Working perfectly with slight tweaks.
I am appreciative of the great help I am getting from this community!

jamesquek

I needed these for a calculation as well.  Here are the fields I created:
Next Month DATEADD(TODAY(),1,'month') *format with no time, use same time zone for all

This Month DATEADD(TODAY(),0,'month') *format with no time, use same time zone for all

Days This Month DATETIME_DIFF({Next Month},{This Month},'days')
Days Gone DATETIME_DIFF(TODAY(),{This Month},'days')
Days Left {Days this Month}-{Days Gone}

Result example

Next Month 11/1/2025

This Month 10/1/2025

Days This Month 31

Days Gone 0

Days Left 31