Use iCloud Keychain to keep information safe on Mac
iCloud Keychain keeps the website login information and credit card information you use with AutoFill in Safari, and the Wi-Fi network information up to date across all your Mac computers (OS X 10.9 or later) and iOS devices (iOS 7.0.3 or later).
iCloud Keychain also stores account settings, so your social media accounts can be added automatically to another Mac when you sign in to iCloud 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 or iOS device unless you approve it.
Set up iCloud Keychain on your Mac
Approve a device to use iCloud Keychain
If you set up iCloud on this Mac, and then you set it up on another device, you may receive a notification on this Mac saying that the other device wants to use your account.
Note: You don’t receive a notification when you set up iCloud Keychain on another device if you’re using two-factor authentication to keep your Apple ID secure. Instead, you allow the device to use your iCloud data simply by entering the login password or passcode for a device where iCloud Keychain is already set up.
On your Mac, do one of the following:
In the notification, click Continue.
On your Mac, choose Apple menu > System Preferences, then click iCloud. Click Options to the right of Keychain, then click Details.
In the dialog that appears, enter your Apple ID and password that you use with iCloud, then click Allow.
Change how new devices can be approved
If there’s an Options button next to Keychain in iCloud preferences, you can change whether your iCloud Security Code can be used to approve iCloud Keychain on new devices. You can also change the iCloud Security Code or the phone number used to verify your identity after you use the iCloud Security Code.
Note: If there isn’t an Options button next to Keychain in iCloud preferences (and iCloud Keychain is turned on), you can’t use an iCloud Security Code. Instead, when you set up iCloud on a new device, you allow the device to use your iCloud data simply by entering the login password or passcode of your Mac or iOS device that already has iCloud set up. In this case, your Apple ID is set up for two-factor authentication, and there’s no need to follow these steps.
On your Mac, choose Apple menu > System Preferences, then click iCloud.
Make sure Keychain is on and your Mac is approved.
Click Options next to Keychain, then make changes in the dialog that appears.
Removing credit card information or account names and passwords in Safari (or with Keychain Access) deletes them from your macOS keychain and from your iCloud Keychain.