A former walk-on running back, Kelce switched to fullback and then finally to offensive line after redshirting his initial year at Cincinnati, seeing action at center and guard in nine games in 2007 as the Bearcats went 10-3 and defeated Southern Mississippi 31-21 in the PapaJohns.com Bowl. As a sophomore in 2008, he made 13 starts at left guard, as part of an offensive line that also included future NFL linemen Jeff Linkenbach and Trevor Canfield, which helped the UC offense average 27.3 points and 375.3 yards of total offense per game. The Bearcats went 11-3 overall, were Big East champions, and played in the FedEx Orange Bowl, where the Bearcats fell to Virginia Tech 20-7. His brother, Travis Kelce, began playing alongside him at Cincinnati after he also joined them in 2008. In 2009, Kelce earned second-team All-Big East honors after starting 13 games at left guard as the Bearcats went undefeated in the regular season and were again Big East Champions, once again earning a BCS Bowl berth, losing to Florida 51-24 in the Allstate Sugar Bowl. He was moved to center for his senior season in 2010 as the Bearcats went 4-8 under new coach Butch Jones. He started the final 38 games of his 47-game Bearcats' career, 26 at left guard and 12 at center. He was named Honorable Mention All-America and second team All-Big East.
Professional career
Despite lacking "true NFL size", Kelce was projected a fourth to fifth round pick. He ran the fastest 40-yard dash time of all offensive linemen at the 2011 NFL Scouting Combine, with a 4.89-second time. On March 11, Kelce had an appendectomy after he was diagnosed with appendicitis. Kelce was selected by the Philadelphia Eagles in the sixth round of the 2011 NFL Draft. Kelce was unable to practice or sign a contract until the NFL lockout was lifted on July 25, 2011. He signed a four-year contract on July 27. New offensive line coachHoward Mudd envisioned Kelce as in the mold of Indianapolis Colts five-time Pro Bowl center Jeff Saturday, whom Mudd coached in Indianapolis for 11 seasons. First-round pick and fellow rookie Danny Watkins compared Kelce to a hedgehog due to his spiky hair and facial hair, in addition to his quickness and stoutness. Kelce battled incumbent starter Jamaal Jackson for the center job early in training camp in August. Kelce received all of the first-team reps in the week before the team's third preseason game. He started in the third preseason game against the Cleveland Browns, and allowed a sack and was penalized for holding. Despite his performance, Kelce was named the starter for the season on August 29. He became the first rookie in Eagles history to start all 16 games at center. In 2012, Kelce was named the starting center for the second consecutive year. On September 16, he suffered a partially torn MCL and torn ACL in a win over the Baltimore Ravens. Kelce would miss the rest of the 2012 season. Kelce had an outstanding 2013 season, starting all 16 games and helping the team reach the playoffs. He helped the Eagles score a team-record 442 points and 6,676 yards. He led the way for the NFL's leading rusher, LeSean McCoy, who rushed for 1,607 yards. Kelce was graded by Pro Football Focus as the best center in the NFL for the season. He was also honored with the Ed Block Courage Award. On February 27, 2014, Kelce agreed to a six-year, $37.5 million contract extension, with $13 million guaranteed, according to agent Jason Bernstein. On September 23, Kelce underwent surgery for a sports hernia and missed 4 games. Despite missing time, he was selected to his first Pro Bowl. In 2015, Kelce started in all 16 games. He was graded by Pro Football Focus as the 7th ranked center in the NFL. In 2016, Kelce started in all 16 games and was selected to his second Pro Bowl. In 2017, Kelce started in all 16 games and had his best season as a pro. He was selected as a First-team All-Pro and was the highest rated offensive lineman by PFF. He also won Run Blocker of the Year by PFF. He won Super Bowl LII with the Eagles after they defeated the New England Patriots 41–33. During the Eagles' Super Bowl parade on February 8, 2018, Kelce garnered national attention after giving an impassioned speech where he defended his teammates, coaches, and front office and compared Eagles fans to hungry dogs who "for 52 years have been starved of this championship," while famously dressed up as a mummer. On March 2, 2019, Kelce signed a one-year contract extension with the Eagles through the 2021 season.
Personal life
He is the older brother of Kansas City Chiefs tight end Travis Kelce. Jason played hockey in high school while brother Travis played basketball. He, along with former Eagle Beau Allen, appeared in the Super Bowl LII-themed episode of It's Always Sunny in Philadelphia, "Charlie's Home Alone", in Charlie Kelly's imagination.