Pittsburgh made the announcement Thursday. Chryst's hiring was widely reported Wednesday.
Pitt was left scrambling for a coach after Arizona State plucked Todd Graham Dec. 14 after his one season with the Panthers. Chryst, 46, was a candidate for Pitt's coaching vacancy last year, and was under consideration for recent openings at Illinois and Kansas.
He joined the Badgers as offensive coordinator and quarterbacks coach in 2005, and was previously Wisconsin's tight ends coach in 2002. He was offensive coordinator at Oregon State from 2003-04 and served as an assistant with the San Diego Chargers from 1999-2001.
Wisconsin averaged 44.6 points, fourth best in the nation, and 467 yards per game this season.
"His remarkable success at Wisconsin is well documented in the form of Big Ten championships and All-America performances," Pittsburgh athletic director Steve Pederson said in a statement Thursday. "But beyond his achievements on the football field, we believed it was important to find a leader who gets the very best from his players while also developing the kind of culture that fits the University of Pittsburgh. Paul Chryst is that leader."
Chryst altered the Badgers' offense to accommodate mobile quarterback Russell Wilson, who transferred from NC State before the season. The new offense helped Wisconsin win the Big Ten championship and earn a trip to the Rose Bowl Game Presented By Vizio to face Oregon.
Chryst will be the fourth Pitt coach in the past 13 months. After Dave Wannstedt resigned Dec. 7, 2010, Pitt hired Michael Haywood, only to fire him 16 days later when he was jailed on a domestic violence charge. Graham was hired Jan. 10.
In addition, interim coach Phil Bennett led the Panthers in last year's BBVA Compass Bowl. Keith Patterson has been interim coach since Graham left for Arizona State. The Panthers (6-6) again will play in the BBVA Compass Bowl, on Jan. 7 vs. SMU.