David Karp (born July 6, 1986) is an American webmaster, entrepreneur, and blogger, best known as the founder and former CEO of the short-form blogging platform Tumblr. Karp began his career, without having received a high school diploma, as an intern under Fred Seibert at the animation company Frederator Studios, where he built the studio's first blogging platform and conceived, wrote, and edited their first internet video network, Channel Frederator. Karp went on to work for online parenting forum UrbanBaby until it was sold to CNET in 2006. Karp then started his own software consulting company, Davidville, where he worked with computer engineer Marco Arment on projects for clients. During a gap between contracts in 2006, the two began work on a microblogging website, which was launched