Janus Friis (b. 1976) is a Danish entrepreneur best known for co-founding the file-sharing application KaZaA, and the peer-to-peer telephony application Skype. In September 2005, he and his partner Niklas Zennström sold Skype to eBay for $2.6bn. They are currently working on Joost - an interactive software for distributing TV shows and other forms of video over the Web.

Before embarking on an entrepreneurial career with Zennström, Friis worked at the help desk of CyberCity, one of Denmark's first Internet service providers. He has no formal higher education since dropping out of high-school before starting the job at CyberCity. Later he worked at Tele2, where he met Zennström.

Friis and Zennström worked together at Tele2 to launch get2net, another Danish ISP, and the portal everyday.com.

After this, the partners decided to leave Tele2 and co-founded Kazaa, the company accountable for the most popular software for use with the FastTrack file sharing network protocol. The FastTrack protocol itself is also codesigned by Friis.

From the success of KaZaA's peer-to-peer technology the duo co-founded Joltid, a software company developing and marketing peer-to-peer solutions and peer-to-peer traffic optimization technologies to companies.

Friis is also co-founder of Altnet, a network that sells commercial music to Kazaa users.

Friis enjoys skydiving, pool, martial arts and winter sea bathing.

Friis was named in Time Magazine 2006 list of 100 most influential people.

He currently works on a new peer-to-peer video distribution service called Joost together with his partner Niklas Zennström.

In 2006 Janus Friis got the prestigious award “IT-prisen” in his home country, given by the Danish IT industry and IDG, for his work and innovation.

He and Zennstrom were also the co-recipients of the 2006 Wharton Infosys Business Transformation Award, given to business and individuals who have used information technology in a way that changed an industry or society as a whole mhjh.