Plz tell me how to use it as Excel's days() function?

[kdb]

I hope use this function in airtable…

please help me out

[Rupert_Hoffsch1]

I think you’re looking for Airtable’s DATETIME_DIFF() function: https://support.airtable.com/hc/en-us/articles/226061308-Supported-unit-specifiers-for-DATETIME-DIFF