He played college football for the Central Michigan Chippewas and Wisconsin Badgers and was selected by the Texans in the first round of the 2011 NFL draft.

Watt was born in Pewaukee, Wisconsin,[1] to parents Connie, a building operations vice president, and John, a firefighter.

[6] Watt attended Pewaukee High School, where he was a four-year letter-winner in football and also lettered in basketball, baseball, and track and field.

[10] Watt followed in his father's footsteps and competed in the shot put during his senior season, earning first-team All-state selection.

[11][12] He captured the state title in the shot put at the 2007 WIAA Division II Championship, setting a new school record with a throw of 59 ft, 11.5 in (18.28 meters).

[21] Overall, in the 2010 season, Watt played in 13 games and led the team in tackles for loss, quarterback hurries, blocked kicks, and forced fumbles.

[69][70] Prior to the start of the 2014 season, the Texans and Watt agreed to a six-year contract extension, worth $100 million.

[72] In a game against the Oakland Raiders, on September 14, Watt became the first defensive player in Texans history to score a touchdown from scrimmage.

Watt picked off a pass from Buffalo's EJ Manuel that was intended for Fred Jackson, and returned it 80 yards for a touchdown.

[79] In a Week 5 Thursday night game against the Indianapolis Colts, Watt recorded two sacks on Andrew Luck, one of which was a strip-sack in the fourth quarter that he recovered and returned 45 yards for a touchdown.

[85] Watt scored his fifth touchdown on November 30, 2014, catching a one-yard pass from Texans quarterback Ryan Fitzpatrick against the Tennessee Titans.

[102][103] With the Texans finishing the season 9–7, the team clinched an AFC South division title but were shut out 30–0 by the Kansas City Chiefs in the Wild Card Round.

He began training camp on the PUP list,[110] but returned in Week 1 to start the season in a victory over the Chicago Bears.

[115] The following day, he underwent back surgery again, and was officially ruled out for the rest of the season after playing three games and recording 1.5 sacks.

[118] During Week 5 against the Kansas City Chiefs on Sunday Night Football, Watt left the game after an apparent leg injury.

[121] During the 2017 season, Watt raised upwards of $40 million for relief and recovery efforts for the Houston area after Hurricane Harvey.

"[123] He was co-named Sports Illustrated Sportsperson of the Year along with Jose Altuve of the Houston Astros for 2017 for their humanitarian and leadership efforts.

This sack forced the Bills, who were up 13–0 at the time, to settle for a field goal rather than a touchdown, allowing the Texans to get back in the game and eventually win it in overtime.

[144] In Week 9 against the Jacksonville Jaguars, Watt recorded his 100th career sack on rookie quarterback Jake Luton during the 27–25 win.

[146] In Week 12, on Thanksgiving against the Detroit Lions, Watt intercepted a pass thrown by Matthew Stafford and returned it for a 19-yard touchdown during the 41–25 win.

[157] Despite experiencing atrial fibrillation on September 28, 2022, and having his heart shocked back in rhythm in a planned procedure the next day, Watt committed to play in Week 4.

Reliant is a retail electric provider in Texas, also a subsidiary of NRG Energy Inc.[166] On February 15, 2018, Baylor College of Medicine announced that Watt would receive an honorary degree from their medical school.

[177] Watt is a fan of Chelsea F.C.,[178] but on May 1, 2023, he and his wife were announced as new minority investors in Burnley F.C., which earned promotion from the EFL Championship to the Premier League for the 2023–24 season.

[186] On November 14, 2014, Watt was nominated for the NFL's Salute to Service Award that honors either a coach, player, or owner for their efforts in supporting the country's servicemen and women.

[187] Due to the extremely good turnout in 2014, the annual Charity Classic has been moved to Minute Maid Park, home of the Houston Astros.

For the 2017 game, Watt invited Arnold Schwarzenegger and swimmer Simone Manuel, a two-time Olympic gold medalist and native of Houston.

The parents, Joshua and Robin Berry, were killed in a head-on collision, and their two sons, Peter and Aaron, were left handicapped.

[191] He also raised over $37 million ($100,000 of which he personally donated) to help Houston recover from Hurricane Harvey, surpassing his initial goal of $200,000.

[192] After the 2018 Santa Fe High School shooting that left eight students and two teachers dead, Watt offered to pay for the funerals of the deceased.

[193] Watt covered the funeral costs for the victims of the Waukesha Christmas parade attack, which left six people dead.