Clear duplicate contacts on multiple computers with Mountain Lion and iCloud

AddressBook Cleaner's users ask us for a solution to remove duplicate contacts from Apple Address Book on Lion and Mountain Lion with iCloud. Since it's a very common problem for users who have upgraded to Lion and used iCloud to keep contacts. The following is a quick step by step guide to finish removal of contact duplicates in such situation:

Remember to backup all contacts before doing the following removal steps

There are 2 steps to delete duplicates from iCloud:

I. Get full copy of contacts on local computer

  • First, go to System Preferences by clicking  -> System Preferences..., then choose iCloud, it will appear like

    Uncheck the "Contacts" surrounded by red line to disable sync Address Book with iCloud, then there will be a message ask for dealing with local contacts.

  • Choose "Keep Contacts" to leave contacts on local computer

  • Re-enable sync Address Book with iCloud by clicking checkbox

  • This time, choose "Merge" to combine contacts from iCloud to make sure we have full copy of contacts.

  • Disable iCloud again as step 2
  • Delete duplicates by using AddressBook Cleaner
  • Now, we have all the contacts on local computer. Repeat steps above to confirm that we have clear copy of contacts on all computers.

II. Update iCloud Contacts

  • Once we have finished getting full copy of contacts on computers, sign in iCloud
  • Choose "Contacts"

  • Delete all contacts in iCloud

    You'd better made a backup by "Export vCard..." before perform the deletion.

    Show the action menu by clicking the button at bottom left corner of the iCloud page.

  • Enable iCloud "Contacts" on your computer (the computer you've done the cleanup in Part I) to update iCloud from local copy of contacts.
  • Done!

    Wait until the update process finishes in step 4. Check to confirm that you have every contact in iCloud "Contacts" as local computer.