The end of Ronaldo's nine-year stay at Madrid was announced on Tuesday by Madrid, with the 33-year-old explaining in an open letter he wants to start a "new cycle" in his career.
Juventus have now confirmed details of the deal, with Madrid to receive €100m for the record goalscorer in the club's history.
Ronaldo hit 450 goals for Madrid, helping the club to win four Champions League titles in the last five seasons.
In addition to the €100m fee, which will be paid over the next two years, Juventus said in a statement that a further €12m will be paid in "additional costs"
Madrid, who have denied making offers for Paris Saint-Germain pair Neymar and Kylian Mbappe, were reported to want the whole Ronaldo fee to be paid in one lump sum.
Ronaldo reached global superstar status after becoming the world's most expensive player when he joined Madrid from Manchester United in 2009.
During his time at the Santiago Bernabeu, Ronaldo won a host of trophies, including two LaLiga titles, and two Copa del Rey crowns.
He helped Madrid to La Decima in the Champions League final with Atletico Madrid in 2014 and played a crucial role in Los Blancos winning the competition in each of the last three seasons.
Ronaldo, a five-time Ballon d'Or winner, will now have the chance to win his third different European league title after completing a shock move to Turin.
Photo Getty Images. Caption: Real Madrid forward Cristiano Ronaldo