Set up iCloud Keychain to autofill information on Mac
iCloud Keychain keeps the website login information and credit card information that you use with autofill in Safari, and your Wi-Fi network information up to date across your Mac, iPhone, and iPad.
iCloud Keychain also stores account settings, so your social media accounts can be added automatically to another Mac when you sign in to your Apple Account on that Mac. For example, Exchange, Google, and other internet accounts you use with Mail, Contacts, Calendar, Reminders, Notes, and Messages can be added automatically.
Everything stored in iCloud Keychain is secure—it’s protected by industry-standard encryption. Your iCloud Keychain can’t be set up on another Mac, iPhone, or iPad unless you approve it.
Set up iCloud Keychain on your Mac
On your Mac, choose Apple menu
If you don’t see your name, click “Sign in,” enter your Apple Account email address or phone number, then enter your password.
Click iCloud, click Passwords, then turn on “Sync this Mac.”
Follow the onscreen instructions to set up two-factor authentication if you haven’t already.
You must also set up your Mac to require a password before you can use iCloud Keychain.
Approve a new device to use iCloud Keychain
If you use two-factor authentication and have already set up iCloud Keychain on another device, you can easily approve a new device to use your iCloud data. On the new device, when prompted, enter the login password or passcode of a device that already has iCloud Keychain set up.
For information about setting up iCloud Keychain on your iPhone or iPad, see the user guide for iPhone or iPad.
Removing credit card information or account names and passwords in Safari (or with the Passwords app) deletes them from your macOS keychain and from your iCloud Keychain.