How do I calculate the duration in days, hours, minutes, between two other custom date fields?

[Eli Devlin]

I have two custom fields, both are date and time pickers.

I would like to be able to calculate the duration of time between the two fields and express it as a third custom field.

I'm currently using a crude automation rule which edits the 'duration' field when the start or end fields are edited, with the value: {{customfield_10999.diff(customfield_11251).hours}}

This returns a number in hours. I could also set it to .days.

But is there a way to return it in minutes, if less than X minutes, hours, if less than X hours, and otherwise days?

Also, which field type would be best for the 'duration' custom field?

Thank you in advance!!

EDIT: I have discovered that simply removing the unit displays the time in all units, as seen here: {{customfield_10999.diff(customfield_11251)}}

However that just leaves the ideal Field Type to use to house this information. I have created a custom field with the Time in Status type, but this field doesn't show up as a target for Edit Field in Automation rules.

Is there a better custom field type to display a time duration?

[Omar Mohamed Fathi · Accepted solution]

1. create a numeric field called ( number of days or number of hours for example ) 

2. create a date picker field ( call it date 1 and memorize its id number for example lets say its number is 123 ) 

3. create a date picker field ( call it date 2 and memorize its id number for example lets say its number is 345 ) 

Now create an automation rule 

trigger issue field value changed or transition to done for example  

actions - edit issue field - choose field date 1 and set the value 

{{now}}

trigger issue created 

actions - edit issue field - choose date 2 field and make it to copy from Resolved field

action - edit issue field - choose field number of hours and make it this value 

{{issue.customfield_123.diff(issue.customfield_345).hours}}

don't forget to change the fields ids according  to you also change the triggers according to your requirements you can also make it days instead of hours 

[Osama]

worked for me

[Eli Devlin]

Thanks Omar, that's really helpful

I decided to use {{customfield_10999.diff(customfield_11251)}}

Without .hours or .days on the end, it actually displays all units.

e.g. 3 days 21 hours 31 minutes,

Thank you!