"It is important for us to thank Donte for all of his contributions to the Cleveland Browns over the last two seasons," Browns executive vice president of football operations Sashi Brown said in a statement. "His passion for this city and dedication to his craft was contagious. These are difficult decisions to make, but we felt it was the best decision for the Browns at this time. We wish him the best as he continues his career."
Whitner, a Cleveland native, took to Twitter to discuss his departure.
Whitner becomes the latest veteran and seventh starter to leave the Browns since the 2015 season ended.
Whitner and inside linebacker Karlos Dansby have been released, and offensive tackle Mitchell Schwartz, receiver Travis Benjamin, safety Tashaun Gipson, inside linebacker Craig Robertson and center Alex Mackleft as free agents.
The Browns must replace both starting safeties from last season, as well as the team's two leading tacklers. Dansby led the Browns with 108 tackles; Whitner was second with 81. Dansby, 34, signed with the Bengals; Whitner, 30, becomes a free agent.
Brown said at the NFL's annual meetings that the team was not looking at age when deciding who stayed.
"It's not a scorched earth policy or a policy just making decisions on a guy's age," Brown said. "We want to look at who can contribute to us. Those guys may come in all different packages and all different ages."
Brown said "we look at it as a build" and not as being in rebuilding mode.
Coach Hue Jackson bristled at the word "rebuild" being used for the team's moves.
"Because I think rebuilding says that you're totally junking everything and starting over, and that's not what we're doing," Jackson said. "I think we're rebooting and we're recharging because there's still Joe Thomases on our football team, there's Danny Sheltons on our football team, there's Joe Hadens on our football team.
"So those guys aren't rebuilding. Those guys have played and they've had success, so I don't see it that way. And I think if we can get the right pieces on our team, you never know what this team could be.
"I know the expectation is low, and deservedly so. I get it, but at the same time, I don't think anybody in our organization is built like that. We like to win, and we want to do everything we can to do that."
Whitner spent the last two seasons with the Browns and made one Pro Bowl after signing as a free agent prior to the 2014 season. In two seasons, he had 187 tackles, one interception and nine passes defensed.
Also Saturday, the team released cornerback Ifo Ekpre-Olomu, a seventh-round pick a year ago who was trying to come back from a devastating knee injury suffered when he was practicing for Oregon's bowl game in December 2014.
The Browns took a chance on him in the draft, based on his previous play. He spent a year dedicated to rehab, but the knee did not come around enough to keep him on the roster.
The Browns also released quarterback Johnny Manziel and receiver Dwayne Bowe this offseason.