Bundled out of Europe by Ajax in midweek, Massimiliano Allegri's men completed a domestic formality thanks to Alex Sandro's first-half header and a German Pezzella own goal eight minutes after the interval.
One point stood between Juve and an eighth-successive Scudetto and they were made to work for all three following Nikola Milenkovic's surprise sixth-minute opener.
The woodwork twice prevented Federico Chiesa from making life more difficult for the Bianconeri, but they shook off the lethargy in the second half to open an insurmountable lead over second-place Napoli.
Juve's confidence, diminished after their loss to Ajax, ebbed further when Chiesa's cross broke perfectly for midfielder Milenkovic to sweep home.
Fiorentina, in contrast, grew in stature, with a combination of the offside flag and the right post denying Giovanni Simeone and winger Chiesa.
The hosts needed inspiration and Alex Sandro provided it with a diving near-post header from Miralem Pjanic's corner in the 37th minute, yet Fiorentina would have surged ahead again had the crossbar not then kept out Chiesa's thumping strike.
23 - Starting from his Serie A debut (September 2015), Alex Sandro has been directly involved in 23 goals (10 goals + 13 assists), more than any other defender. Push.#JuventusFiorentina #SerieA pic.twitter.com/UbBmdCzNl2— OptaPaolo (@OptaPaolo) April 20, 2019
The tension was released soon after the interval. Cristiano Ronaldo found space to the right of goal and defender Pezzella turned the attacker's pass into his own net.
Juve were suddenly emboldened by belief and Pjanic, Ronaldo and Juan Cuadrado all saw shots blocked in quick succession.
Their Portuguese superstar ultimately went unrewarded in his attempts to score his 600th club goal, but that can be put on hold as the Bianconeri uncork the champagne.
What does it mean? Allegri worthy of adulation
Allegri was forced to defend his Juve record following the surprise quarter-final exit to Ajax in the Champions League.
While continental success is still clearly the major prize, the ex-AC Milan boss deserves his share of plaudits for juggling egos and orchestrating the most serene of title triumphs, his sixth overall in Serie A.
Chiesa exudes class
Still just 21, Fiorentina forward Chiesa is again being mentioned in transfer rumours as the off-season approaches.
Suitors will be lining up based on the strength of his performance here, which included forcing the opening goal, two shots that came back off the woodwork, and several more flashes of mesmerising ability.
It came as a major surprise that Vincenzo Montella withdrew his most dangerous player with 24 minutes to play.
Rusty Cuadrado loses his radar
Making a rare start in a season inhibited by fitness issues, the fleet-footed Cuadrado will have only finished this match with a greater sense of personal frustration.
His shooting was wild and rushed, the signs of a player desperate to impress but lacking sharpness.
Key Opta Facts
8 - #Juventus have now won 8 Serie A championships in a row, setting a new record within the top-5 European Leagues – surpassing their own current run as well as Lyon’s between 2001/02 to 2007/08 (7 in a row). Infinity.#JuventusFiorentina #SerieA pic.twitter.com/DnDdK3jusA— OptaPaolo (@OptaPaolo) April 20, 2019
- Juventus have equalled the record as earliest title winners in Serie A in the three-points era – same as Inter in 2006-07.
- They have now played 150 Serie A matches at the Allianz Stadium, recording 127 wins (85 per cent) and scoring 335 goals.
- Since his Serie A debut (September 2015), Alex Sandro has been directly involved in 23 goals (10 goals and 13 assists), more than any other defender.
- Only Borussia Dortmund and Sassuolo (both 18) have scored with more different players than Juventus (17) in the top-five European leagues in 2018-19.
- Juventus and AC Milan are the two teams to have benefited from the most own goals in the current league season (four each).
Juve make the trip to Milan for a date with Inter next Saturday.