Copies of existing UDFs can be created using the ‘Save As’ function, which allows the user to save the current settings of a UDF and creates a clone or copy, The user can then rename it, so that a new record can be created from duplicating the current UDF.
To create a new UDF using the Save As function, follow the steps below.
Go to Admin > Configuration Data Management > Data Dictionary Management - Fields.
The Data Dictionary Fields Management page will display with the object grid populated with the list of all standard and UDFs across objects.
Search/Filter/Sort the grid for the field you would like to copy.
Click the Save As icon next to the field name. Click the Save button to save the field. Or, click the Cancel button to exit without saving.