In an article on The Players' Tribune, Peppers said:
"Anybody who knows me knows I'm not big on words and I don't like to put myself out there, so I'm just gonna get right to it.
"Seventeen years is a long time to be playing this game. It's two careers for a lot of people. I'm thankful that I have been able to play so long and still be healthy. I'm not all banged up and beaten down. I still feel good.
"But as much as I would love to play forever, I know that I can't. It's gotta end at some point. That point is now. Today, I'm retiring."
Peppers played for the Carolina Panthers, Chicago Bears and Green Bay Packers from 2002 to 2018. He spent the bulk of his career with the Panthers, who drafted him No. 2 overall and brought him back in 2017.
Even though Peppers played last season at the age of 38, he remained one of the NFL's best pass-rushing specialists. The North Carolina native finished second on the Panthers with five sacks.
Per Pro Football Focus, Peppers ended 2018 with the fourth-highest overall grade (75.9) among all Carolina defensive players.
Peppers is one of five players in NFL history with at least 150 sacks. The others on the list include Bruce Smith, Reggie White, Kevin Greene and Chris Doleman, all of whom have been elected to the Pro Football Hall of Fame.
Peppers has another feather in his cap as the only player in NFL history with at least 150 sacks and 10 interceptions. He also only had two seasons with fewer than seven sacks.
Despite Peppers' age, his Panthers teammates were frequently in awe of what he was able to do.
"I think he still looks like the Pep of old, man, with the way he goes out and has the ability to dominate football games," Panthers linebacker Thomas Davis told Dan Wiederer of the Chicago Tribune in October 2017.
Over his 17 years in the NFL, Peppers was named to the Pro Bowl nine times and the All-Pro First Team three times. He was also included on the NFL's All-Decade team for the 2000s and has a case to be part of the group for the 2010s.
Now that the book has been closed on Peppers' career, he can prepare his speech for the Pro Football Hall of Fame as soon as he's eligible in five years.