Determining the "most popular" Tumblr blog can be subjective and may change over time. Additionally, Tumblr does not publicly provide a comprehensive ranking system for blogs based on popularity. However, I can mention some notable Tumblr blogs that have gained significant attention and followers:
1. "Humans of New York" (humansofnewyork.tumblr.com): The Humans of New York blog features photographs and stories of people living in New York City. It has gained immense popularity for its compelling portraits and the narratives shared by the individuals photographed.
2. "The Art of Animation" (theartofanimation.tumblr.com): This Tumblr blog showcases a wide range of beautiful and captivating animated artwork from various artists, studios, and styles.
3. "The Mind Unleashed" (themindunleashed.org): While not exclusively a Tumblr blog, The Mind Unleashed curates and shares a wide range of thought-provoking and inspiring content covering various topics such as science, spirituality, and social issues.
4. "Black Girls Killing It" (blackgirlskillinit.tumblr.com): This blog celebrates and showcases the beauty, style, and accomplishments of black women. It has gained a significant following for its empowering content.
It's important to note that popularity on Tumblr can vary depending on different factors such as niche, content focus, engagement, and timing. Additionally, new blogs may gain prominence over time. Therefore, the "most popular" Tumblr blog can be subjective and subject to change.