The new terms are reportedly worth around $48million to Bitonio, who says he is hoping to finish his career in Cleveland.
The 30-year-old was a second-round NFL draft pick in 2014, having played college football at Nevada.
"I've been here for eight years now and seen a lot of ups and downs," Bitonio said in a statement. "To be part of that and for the team to have faith in me and allow me to be here for my entire career, it really means a lot. It's special.
"You see guys switch teams a lot and go from team to team, great players in this league. I saw Joe Thomas end his career here.
"It's something when you get into Year 8 and Year 9, it gets in the back of your mind where it'd be really special to be in Cleveland your whole career and try to win a championship with these guys.
"I just want to thank the Haslams, Andrew Berry and Coach [Kevin] Stefanski for having faith in me and providing me with this opportunity.
"I've got a lot of good friends on the O-line, and it's guys who work hard and love the game of football and are passionate about the Cleveland Browns.
"We want to run the ball, we want to protect Baker [Mayfield] and take our shots down field. There's sometimes a lack of good linemen in the league, so to get five, six, seven good ones on a team, it's really nice to have that depth and hopefully we can keep the guys together for as many years as possible."
Bitonio's extension comes just after fellow guard Wyatt Taylor was tied to a four-year extension worth $56.8million on Tuesday as Browns general manager Andrew Berry looks to lock down key players.
"After last season, we decided that one of our major football priorities would be to make Joel Bitonio a Brown for the rest of his career," Berry said in a statement.
"Joel is one of our most decorated players and is the ideal personification of our 'Tough, Smart, Accountable' mantra. We value Joel's high-level performance, leadership, consistency and durability.
"We are all excited about this extension and hopeful that at the end of his career we will all be looking forward to celebrating Joel's gold jacket fitting in Canton."
It is the first time a selection has been made exclusively by players, with the most recognised All-Pro team being the one generated by votes from NFL writers and broadcasters, organised by the Associated Press.
NFLPA president J.C. Tretter issued a statement on Tuesday outlining why he felt it was important for players to have their say.
"For the first time ever, NFL players are honouring the best in the game by naming our Players' All-Pro team," he said. "Every active NFL player had the opportunity to cast their vote to decide who is really the best at each position.
"We compete against each other all season long, watching hours and hours of film week after week after week, and yet we have never had an opportunity to truly use our expertise to select the best of us.
"We think it is important that players take the time to define ourselves, because so far, we have allowed everyone else to either pick or dilute our voices."
The team was unveiled on Wednesday, with selections including Kansas City Chiefs quarterback Mahomes, Las Vegas Raiders running back Josh Jacobs, and his team-mate Davante Adams and Minnesota Vikings' star Jefferson as wide receivers.
The Chiefs and the San Francisco 49ers were the best represented teams, with four players each.
2022 Players' All-Pro Team – Quarterback: Patrick Mahomes (Kansas City Chiefs), Running back: Josh Jacobs (Las Vegas Raiders), Fullback: Kyle Juszczyk (San Francisco 49ers), Wide receivers: Justin Jefferson (Minnesota Vikings), Davante Adams (Las Vegas Raiders), Tight end: Travis Kelce (Kansas City Chiefs), Left tackle: Trent Williams (San Francisco 49ers), Left guard: Joel Bitonio (Cleveland Browns), Center: Jason Kelce (Philadelphia Eagles), Right guard: Zack Martin (Dallas Cowboys), Right tackle: Lane Johnson (Philadelphia Eagles), Edge rushers: Nick Bosa (San Francisco 49ers), Myles Garrett (Cleveland Browns), Interior defensive linemen: Chris Jones (Kansas City Chiefs), Aaron Donald (Los Angeles Rams), Nose tackle: Dexter Lawrence (New York Giants), Off-ball linebackers: Fred Warner (San Francisco 49ers), Roquan Smith (Baltimore Ravens), Cornerbacks: Pat Surtain II (Denver Broncos), Darius Slay (Philadelphia Eagles), Free safety: Minkah Fitzpatrick (Pittsburgh Steelers), Strong safety: Derwin James Jr (Los Angeles Chargers), Kick returner: Cordarrelle Patterson (Atlanta Falcons), Punt returner: KaVontae Turpin (Dallas Cowboys), Core teamers: Jeremy Reaves (Washington Commanders), Justin Hardee (New York Jets), Kicker: Jason Myers (Seattle Seahawks), Punter: Tommy Townsend (Kansas City Chiefs), Long snapper: Morgan Cox (Tennessee Titans).
