The answer can only be approximated and also depends on what is defined as a computer. The website InternetWorldStats.com estimates that 2,405,518,376 people, or 34.3 percent of the world's population, are Internet users, meaning they have access to the Internet either through a computer or mobile phone.
Computer and Internet penetration varies significantly from region to region in the world. In North America, 78.6 percent of the population has access to the Internet, compared to just 15.6 percent in Africa. Asia, as a continent, has the largest overall number of Internet users (over one billion), making up around 44.8 percent of the world total.