Because the login Keychain and user account passwords are identical by default, you may want to change your login Keychain password if another person learns your user account password. Even if no one else currently knows your password, you may want to change it periodically to keep it secure. You change your Keychain passwords in the Keychain Access utility on Mac OS X Yosemite. If you have forgotten your Keychain password, you cannot reset the password but must discard the old Keychain and create a new one.
Open the "Utilities" folder under Applications.
Double-click "Keychain Access." Keychain Access may require you to enter your user password to unlock the utility if you previously locked it.
Choose the Keychain for which you want to change the password; right click it and select "Change Password for Keychain "Login," where "Login" is the name of the Keychain you chose.
Enter your current password once and the new password twice. Click "OK" to change the password for the Keychain.
Click "Preferences" from the Keychain Access drop-down list.
Click "Reset My Default Keychain" under the General tab.
Enter your log-in password and click "OK."
Click "OK" to create a new login Keychain. The old Keychain has been renamed and moved.
Quit "Keychain Access" and restart your computer to make the change take effect.
Tips & Warnings
- To delete any individual key from Keychain Access, select the key and press the delete key. Choose "Delete" from the confirmation window.
- Administrators can change user login passwords, but not Keychain passwords. When an administrator changes a user's login password, the user has to enter or update his Keychain password when he next logs in.