Frolik's deal is worth US$4.3 million annually. Ramo will earn $3.8 million on a one-year deal.
Those moves came a day after Calgary announced newly acquired defenceman Dougie Hamilton signed on for six years and $34.5 million.
Frolik, 27, is coming off back-to-back 42-point seasons with the Winnipeg Jets. The right-winger played all 82 games this past season for 19 goals and 23 assists. His plus-minus was plus-8. The six-foot-one, 200-pound Czech was held pointless in four playoff games.
Flames general manager Brad Treliving compared Frolik to a "Swiss Army Knife."
"He's able to do a lot of different things that are very valuable," Treliving said. "He probably is not going to be a guy that scores you 30 goals, but he's going to do a lot of the heavy lifting in some of the areas that aren't so sexy that help you win games."
Frolik was paid $3.3 million in 2014-15.
"Calgary has a lot of talent. I had a good feeling about them," Frolik told The Canadian Press from Florida. "I talked to (Flames forward) Jiri Hudler too and he said the city is great and the organization is perfect too.
"They did the right steps last year and I think they've got a bright future in front of them and that's why I chose Calgary. I'm looking for success there."
Frolik won a Stanley Cup with the Chicago Blackhawks in 2013, when he had three goals and seven assists in 23 playoff games. He's compiled 95 goals and 140 assists in 512 career games with Florida, Chicago and Winnipeg.
The Flames also signed centre Derek Grant, who played last season in the American Hockey League for the Binghamton Senators, to a one-year contract. Calgary dealt minor-league forward Max Reinhart to Nashville Predators for a conditional fourth-round draft pick.
Ramo, who turned 29 on Wednesday, posted a 15-9-3 record, a 2.60 goals-against average and a .912 save percentage in his second season in Calgary.
The Finn replaced Jonas Hiller during Calgary's second-round playoff series against the Anaheim Ducks.
Ramo raised his stock for free agency averaging 2.86 goals against per game and a save percentage of .906 in seven post-season appearances.
Instead of testing the open market, the six-foot-two, 206-pound goalie opted to return to Calgary for a raise on his $2.75 million salary last season.
"The only thing this team is going to do is get better, so I wanted to come back," Ramo said. "Obviously it's a one-year deal . . . you have to try to fit in somewhere and I felt really comfortable signing a one-year contract."
The market for free agent goaltenders altered when seven goalies changed hands at last weekend's NHL entry draft in Florida. Jhonas Enroth signed a one-year deal with the Los Angeles Kings on Wednesday to back up Jonathan Quick.
Hiller has a year remaining on his contract. Minor-leaguer Joni Ortio has expressed a desire to compete for Calgary's starting job at training camp in September. Ortio, 24, went 4-1 in a mid-season call-up when Ramo was injured.
"What we feel with bringing Karri back is we've strengthened the position, we've stabilized the position again," Treliving said. "We've got three capable goaltenders to go out and win us games.
"I don't envision a situation (that) we're going to go the next 10 months just carrying three goaltenders. It gives us options. We have those players and the capital of those players."
Hiller went 26-19-4 starting the majority of games, with a goals-against average of 2.36 and a save percentage of .918.
The 33-year-old Swiss netminder was Calgary's starter in the first round of playoffs Vancouver, but was on the bench the last four games of the second round against Anaheim.
Ramo made 44 saves in Calgary's final game of the season — a 3-2 overtime loss to the Ducks.
"I feel I have way more to give," Ramo said. "That's what I need to show now. The way the year ended, I'm really looking forward to next season."
Stephen Whyno in Toronto contributed to this story.
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