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Log into your Jira Cloud instance.
Click on the cog icon to see the Settings menu.
Go to Issues under Jira Settings.
Go to the Custom Fields menu under the Issues section in Jira Settings.
Click ... in the row of the Duration Field and select Contexts and Default Value.
The Configure Custom Fields page will appear.
Click Edit Default Value.
The Jira Set Custom Field Defaults screen will appear.
Enter a default value for the Duration Field.
Click Set Default, and that’s it!
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