Hi @Arvind Pandey,
There is some information available about the use of your custom fields out of the box, although it does indeed require some digging into.
If you head over (as an admin) to Settings > Issues > Custom fields, you get the list of all custom fields in your instance, split across active and trashed:
You can sort the list by clicking the column headers. Especially the last two columns do provide you with some information about usage:
Screens and context
If a field is not on any screens, you can be quite sure that - at least currently - it is not being used.
The last date any information is shown here should represent the last time information was entered through this custom field. No information or Not tracked are an indication that the field probably does not contain any data.
To be on the safe side, there is nothing wrong with double checking using JQL on fields you have doubts about. Such a filter would be e.g:
CAB is not EMPTY
This would return all issues across your Jira instance that have a value. In this case you would expect zero results.
Note: be sure to perform the search with an account that has access across all projects. Your search will only return issues you have access to!
welcome to the Atlassian Community!
On Cloud (especially Cloud Free plan) the possibilities are a bit restricted. On a server environment there were several Apps providing this as well as the possibility to access the database. While this was never really recommended in some rare cases this allowed additional insights - done best on a replica which was non-productive (and additional caution).
For cloud there is still "Optimizer" available from Marketplace.
Please note that this App is a commercial one and you would need to pay some extra money if you want to go this way.
Well, as for Jira cloud natively - I guess there is some manual inventory needed. You could check using JQL if there are unused custom fields, look at several Jira projects, talk to the users.
I found an additional cleaning up article:
You could read through the steps by means of a high-level guide - many information are aimed towards Server as well, but some are applicable to Cloud as well.
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events