If you have encountered data loss of iPhone or have a strong sense of preventing data loss, you may keep in mind to regularly backup your iPhone. While your music, photos, games, apps, etc. are important to you, your contacts are probably the most important out of anything stored on your iPhone.
There are several different methods you can use to backup iPhone contacts. To backup iPhone contacts via iTunes, you’ll essentially backup all data on your iPhone since it doesn’t allow you to simply backup just your contacts. To backup iPhone contacts from iCloud can be great since it can sync your contacts across Apple devices. However, when you lose your contacts and want to either "Restore from iCloud Backup" or "Restore from iTunes Backup", you cannot restore contacts only.Here, I'm highly recommend iPhone Transfer for you. iPhone Transfer can works perfect in iPhone contacts backup. It allows you to backup contacts only and you can restore contacts with one click. Moreover, you can edit, delete, organize and add contacts quickly with the keyboard on your computer.
OR: Click "Contacts" tab in the left sidebar. Choose the contacts you want to backup and lick "Import/Export" > "Export Selected Contacts" or "Export All Contacts", then choose the contact format (vCard, CSV) in the pull-down list to save them on your computer.