You can change your user name very easily just going to
Applications -> System Preferences -> Users & Groups...
If you want to change the name of your computer in your network as well, you should go to
Applications -> System Preferences -> Sharing...
But, if what you want is to change your account name (i.e., the name of your home folder), that's a bit more complex. According to this article, you could do this workaround (Mac OS X v10.5 or later):
- Enable the root user.
- Log in as root.
- Navigate to the /Users folder.
- Select the Home folder with the short name you want to change, and rename it just like you would rename any folder. Keep in mind that the
account name must be all lowercase, with no spaces, contain only
letters or contain a mix of letters and numbers, and it cannot be the
same as an existing user's Full Name.
- Use the Users & Groups pane (Accounts pane in Mac OS X v10.6.8 or earlier) in System Preferences to create a new user with the Account
name or Short Name that you used in the previous step.
- Click OK when "A folder in the Users folder already has the name 'account name'. Would you like to use that folder as the Home folder
for this user account?" appears. Note: This will correct the ownership
of all files in the Home folder, and avoid permissions issues with the
- Choose Log Out from the Apple menu.
- Log in as the newly created user. You should be able to access all of your original files (on the desktop, in Documents, and in the other
folders of this Home).
- After verifying that your data is as expected, you can delete the original user account via the Users & Groups pane (Accounts pane in
Mac OS X v10.6.8 or earlier).
- Disable the root user.