Tumblr blogs are very flexible to use. Besides you can create ten additional secondary blogs, you can also change the name of your main blog whenever you want. By changing the name of a Tumblr blog, you will also change its URL address.
Step
Part 1 of 2: Deciding to Change Your Tumblr Name
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Step 1. Don't change your blog name unless you don't have a problem with changing the URL address on your Tumblr account as well
All link addresses linked to the previous name will no longer work. If you share a lot of links from your blog, consider creating a secondary blog instead of renaming your Tumblr.
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Step 2. Set the name you want to use to replace your previous Tumblr name
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Step 3. Add a secondary blog to your newly created Tumblr account name if you want to keep your old blog name
Tumblr will retain your old account name for 24 hours only. If you don't create a secondary blog with that name, then other people will be able to use it.
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Step 4. You don't have to worry about losing followers
Changing your Tumblr name won't take away your follower count. However, it's a good idea to let your followers know that your Tumblr name and URL have changed in your next post to prevent confusion.
Part 2 of 2: Changing the Tumblr Name
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Step 1. Sign in to Tumblr.com
Sign in with your account.
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Step 2. Click the Settings option at the bottom of your account menu
This option is located on the dashboard.
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Step 3. Select the blog you want to rename
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Step 4. Go to the username section
Hover your cursor until you see the pencil icon. Click the icon.
On one of the secondary blogs, this section is referred to as the Tumblr URL
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Step 5. Type the new name you want to use
Click “Save.” Now, your Tumblr name has changed.