Koum was born in Kyiv, Ukraine. He grew up in Fastiv, outside Kyiv, and moved with his mother and grandmother to Mountain View, California in 1992, where a social support program helped the family to get a small two-bedroom apartment, at the age of 16. His father had intended to join the family later, but finally remained in Ukraine.
San José State University.
In 2014, he entered the Forbes list of the 400 richest Americans at position 62, with an estimated worth of more than seven and half billion dollars. He was the highest-ranked newcomer to the list that year. He is Jewish. At first Koum"s mother worked as a babysitter, while he himself worked as a cleaner at a grocery.
By the age of 18 he became interested in programming.
He enrolled at San Jose State University and simultaneously worked at Ernst & Young as a security tester. In February 1996, a restraining order was granted against Koum in state court in San Jose, California.
An ex-girlfriend detailed incidents in which she said Koum verbally and physically threatened her. In October 2014, Koum said about the restraining order, "I am ashamed of the way I acted, and ashamed that my behavior forced her to take legal action."
In 1997, January Koum was hired by Yahoo as an infrastructure engineer, shortly after he met Brian Acton while working at Ernst & Young as a security tester.
Over the next nine years, they worked at Yahoo.
In September 2007 Koum and Acton left Yahoo and took a year off, traveling around South America and playing ultimate frisbee. Both applied, and failed, to work at Facebook. In January 2009, he bought an iPhone and realized that the then-seven-month-old App Store was about to spawn a whole new industry of apps.
Koum almost immediately chose the name WhatsApp because it sounded like “what’s up,” and a week later on his birthday, February
24, 2009, he incorporated WhatsApp Incorporated. in California. WhatsApp became popular in just a small amount of time, and this caught Facebook"s attention.
The two began meeting at a coffee shop in Los Altos, California, then began a series of dinners and walks in the hills above Silicon Valley. On February 9, 2014 Zuckerberg asked Koum to have dinner at his home, and formally proposed Koum a deal to join the Facebook board - 10 days later Facebook announced it was acquiring WhatsApp for United States$19 Billion United States dollar. His mother died in 2000 of cancer in the United States, while his father died in Ukraine in 1997.
January Koum was part of a group of hackers called w00w00, where he met the future founders of Napster, Shawn Fanning and Jordan Ritter.
In November 2014, Koum donated $1,000,000 to The FreeBSD Foundation, and close to $556 million to the Silicon Valley Community Foundation (SVCF) the same year.
