Toronto, which has won six straight games and eight of nine, also got 14 points and 10 rebounds from Serge Ibaka.
The Raptors closed the decisive third quarter on a 21-4 run, giving Toronto a 17-point lead. Miami made it close in the final minutes, using a 13-0 run.
A Wayne Ellington 3-pointer with 6.6 seconds left cut Toronto's lead to 114-112. CJ Miles made one free throw, and Miami's Josh Richardson raced upcourt, missing a 3-pointer off the back iron that would have sent the game to overtime.
With the win, the Raptors have the best home record in the NBA at 24-4, and they avenged a 90-89 Air Canada Centre loss to Miami on Jan. 9.
The game was billed as a possible first-round playoff preview since the Raptors have the best record in the Eastern Conference -- No. 3 in the NBA -- and Miami entered the game in the No. 8 spot.
In terms of average points per game, Toronto has the most potent Eastern Conference offense since the 1991-92 Raptors, and that was apparent early as Miami trailed 28-24 after the first quarter.
However, Miami rallied in the second and led by as many as eight points. But that was Miami's last lead, as the Raptors closed the first half on a 13-4 run to take a 57-55 lead into the break.
Lowry scored 13 points in the first half, including two 3-pointers in the final 28 seconds. The second of those two shots came as the halftime buzzer sounded. Lowry was crowded by Dragic but still managed to lift a shot from the top of the key, swishing his opportunity as the crowd roared.
DeRozan, who scored just seven points in the first half, atoned with a 19-point third quarter. DeRozan, who entered the game with a team-best 23.9 scoring average, helped the Raptors close the third with a 98-81 lead.
The 41 points scored in the third by Toronto were the most allowed in any quarter this season by Miami, and it was too big a hole to overcome despite a valiant Heat effort in the fourth.
--Field Level Media