1) Open and sign in to the Tumblr App.
2) Tap on the User icon in the bottom corner.
3) Select the Settings icon from the icons at the top of the Tumblr App to access the Account section.
4) Now, tap on the Change name option to rename your Tumblr blog.
5) Enter your preferred name and tap Save.
1) Open Tumblr.com and sign in on your preferred browser.
2) After logging in, hover on your profile picture and click on the Settings icon. (Refer to below image)
3) Click on the Pencil icon to edit your Username.
4) Finally, click Save to apply changes.
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