Tumblr does not allow you to create a completely private account. However, you are allowed to create private blogs and posts that are only shared with users who have your permission to view them.
There are two aspects of locking down your Tumblr privacy settings — account management and blog privacy.
Manage account settings by clicking on the profile icon on the top right corner of any page. Use the dropdown menu to select “settings.”
The settings tab will bring you to the account management section. Use this section to enhance privacy and prevent unauthorized access of your Tumblr account.
Email search: Prevent individuals from finding your blog by way of searching your email address when you disable this setting.
Password: Create a strong, unique password that contains a combination of uppercase and lowercase letters, numbers and symbols. Change your password at least every 90 days.
Email notifications: Enable email notifications about account activity. These notifications will tip you off to a potential hacker.
Two-factor authentication: Enable this feature to add an extra layer of security. Then, when you log in, a 6-digit PIN will be sent to your phone to act as a second password.
Apps: Select “apps” from the right sidebar to restrict third-parties from using your Tumblr data.
While the Tumblr privacy settings prohibit private accounts, you may create a secondary blog that is private — allowing only users that know a password to access it. This password is not the one you use to log in.
First, open your dashboard and click on the profile tab to the left.
Select “+New” to create a new blog. This secondary blog will give you the option to make it private.
You will be directed to this page to create your new blog. Select “password protect this blog” and enter a desired password that you may share with followers you pre-select to view content on this secondary Tumblr blog.