Tumblr
A microblogging platform known for progressive content and reblog culture.
Tumblr (pronounced TUM-blər) is a microblogging and social media platform launched in 2007 by David Karp. It is now owned by Automattic through its subsidiary Tumblr, Inc. Users can share multimedia and other content in a short-form blog format. The site has drawn both attention and controversy for its large amount of progressive user-generated content.
Development started in 2006 during a two-week break between contracts at Karp’s consulting firm, Davidville. Karp had long been interested in tumblelogs (short-form blogs, which inspired the name) and had waited a year for an existing blogging platform to introduce one. When none did, he and developer Marco Arment built their own. Tumblr launched in February 2007 and gained 75,000 users within two weeks. Arment left in September 2010 to focus on Instapaper. In May 2012, Tumblr ran its first major brand ad campaign with Adidas, who created an official soccer blog and bought dashboard ad placements—just two months after the company announced it would start selling ads.
In May 2013, Yahoo! Inc. agreed to buy Tumblr for $1.1 billion in cash. Many users were unhappy, starting a petition that gathered nearly 170,000 signatures. David Karp stayed on as CEO, and the deal closed on June 20, 2013. Advertising revenue targets were missed, and in 2016 Yahoo wrote down $712 million of Tumblr’s value. Verizon Communications bought Yahoo in June 2017, placing Tumblr under its Oath subsidiary. Karp announced his departure in November 2017, and president and COO Jeff D’Onofrio took over. The site, along with the rest of Oath (renamed Verizon Media Group in 2019), continued to struggle. By March 2019, Similarweb estimated Tumblr had lost 30% of its user traffic since December 2018, when it introduced stricter content rules that heavily restricted adult content—a notable draw for the service. In May 2019, reports emerged that Verizon was considering selling the site, and Pornhub’s vice president publicly expressed interest in buying it and reinstating the previous adult content policies.
In August 2019, Verizon Media sold Tumblr to Automattic, the company behind WordPress.com and the open-source WordPress software. The sale price was undisclosed, but Axios reported it was under $3 million—less than 0.3% of Yahoo’s original purchase. Automattic CEO Matt Mullenweg said Tumblr would complement WordPress.com and that the conten
- founded
- 2007
- founder
- David Karp
- type
- Microblogging and social media platform
- current_owner
- Automattic (since 2019)
- notable_acquisition
- Acquired by Yahoo! in 2013 for $1.1 billion
- key_feature
- Dashboard with reblogging and tagging system
Lore & Background
Development of Tumblr began in 2006 during a two-week gap between contracts at David Karp's software consulting company, Davidville. Karp had been interested in tumblelogs for some time and, after a year of waiting for established platforms to introduce their own, he and developer Marco Arment began working on their own platform. Tumblr was launched in February 2007 and within two weeks had gained 75,000 users. Arment left the company in September 2010 to work on Instapaper. In May 2012, Tumblr featured its first major brand advertising campaign with Adidas, two months after announcing a move toward paid advertising.
Reader's Guide
Tumblr's significance lies in its role as a hub for short-form blogging and progressive user-generated content, which brought both attention and controversy. Its ownership history reflects the challenges of monetizing such a platform: Yahoo! acquired it for $1.1 billion in 2013, but advertising goals were not met, leading to a $712 million write-down in 2016. After Verizon's acquisition of Yahoo in 2017, Tumblr struggled further, losing 30% of user traffic after a stricter content policy on adult content was introduced in December 2018. In 2019, Automattic purchased Tumblr for less than $3 million, less than 0.3% of Yahoo's original price. Under Automattic, the platform has focused on core functionality, integration with WordPress, and plans for decentralized social networking via ActivityPub. The platform's unique tagging system, used for both description and commentary, and its dashboard-based reblogging culture have defined its user experience. Recent changes, such as selling user data to AI companies and a 2026 reblog note change that was quickly rolled back, highlight ongoing tensions between user expectations and corporate direction.
Did You Know?
- Tumblr was launched in February 2007 and gained 75,000 users within two weeks.
- In 2024, Automattic licensed public posts from Tumblr for AI training, with users given the option to opt out—contrary to rumors that data was sold to Midjourney and OpenAI with default opt-in.
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