I used this to get a solution
https://calderaforms.com/doc/cf-state-cf-events-caldera-forms-javascript/
Scroll down to “Setting Caldera Forms Field Values With Custom JavaScript”
basically used that code to grade the second date field, grabbed the first date using
var myFirstDate = document.getElementById(‘fld_9286715_1’).value
turned both dates into days
var myFirstTimeStamp = (new Date(myFirstDate).getTime())/86400000; //convert ms to days
var mySecondTimeStamp = (new Date(value).getTime())/86400000; //convert ms to days
subtract first date from second date and output days to a new field
Just added the script to the header, works for my needs, probably a better solution but I’ll worry about that another time, just needed my form to work
I’m looking for the same thing, user enters two dates and would like to check the length time in between.