Allen was born on January 16, 1995, in Anniston, Alabama, living in Seattle, North Carolina, South Carolina, Pittsburgh, and Maryland before settling down in Ashburn, Virginia, and attending Stone Bridge High School.[1] Allen's parents split up when he was three years old and his mother was granted custody of him and his brother, Richard Allen III. At the age of eight, both he and his brother were taken away by child protective services.[2] Allen spent ten months in foster care before his father, US Army Sgt. 1st Class Richard Allen Jr., won full custody of him and his brother in 2004.[2][3] As a senior in 2012, he was the Virginia Gatorade Football Player of the Year.[4] During his career, he had 308 tackles and 44 sacks. Allen was a five-star recruit and was ranked amongst the top of his class.[5] He committed to play college football for the University of Alabama.[6][7]
Allen was projected to be a top five pick by some NFL draft experts. His stock began to decline after teams became concerned when he was diagnosed with arthritis in one of his shoulders and had surgery on both, two weeks before the combine.[10] He was ranked as the top defensive tackle by Sports Illustrated, Pro Football Focus, and NFLDraftScout.com.[11][12][13]ESPN ranked him the second best defensive lineman behind Myles Garrett.[14] Even with the arthritis diagnosis, Allen was projected to be a first-round pick by analysts and scouts.[15]
Allen returned for the 2018 season and started all 16 games, recording eight sacks, 61 total tackles, and 15 quarterback hits.[22] In the 2019 season, he started in 15 games. He finished with six sacks, 68 total tackles (46 solo), one pass defended, one fumble recovery, and one fumble recovery.[23] The team exercised the fifth-year option on his contract on April 27, 2020.[24] After playing the defensive end position for the first three seasons of his career, Allen switched over to defensive tackle after the team's new defensive coordinator Jack Del Rio implemented a 4-3 defensive scheme.[25][26] He finished the 2020 season with two sacks, 63 total tackles (36 solo), one fumble recovery, and one safety.[27]
On July 27, 2021, Allen signed a four-year contract extension worth $72 million.[28][29]
On December 13, 2021, he was placed on the COVID-19 reserve list, but placed back on the active roster five days later.[30][31] After recording a sack in the Week 15 game against the Philadelphia Eagles, he set a new career high of 8.5 sacks in a single-season.[32] Allen punched teammate Daron Payne on the sideline during a blowout Sunday Night Football loss to the Cowboys in Week 16.[33] He was voted to the 2022 Pro Bowl, his first, following the season.[34] He was ranked 88th by his fellow players on the NFL Top 100 Players of 2022.[35]
In Week 1 of the 2022 season, he recorded three tackles and a sack.[36] Allen recorded his first career interception on Justin Fields and first career forced fumble in the Week 6 win over the Chicago Bears.[37] In December 2022, he was voted into his second consecutive Pro Bowl.[38] He was ranked 52nd by his fellow players on the NFL Top 100 Players of 2023.[39]
In the 2023 season, Allen started 16 games. He finished with 5.5 sacks, 53 total tackles (30 solo), and one pass defended.[40]
Allen married his wife, Hannah, in July 2018.[41] Due to his own personal experience with the foster care system, Allen has often helped with homeless shelters.[42][2]
Allen grew up as a fan of the Washington Redskins, the same team that drafted him in the first round.[43]