It is the Devils' longest winning streak since they won 11 in a row in 2005-06. They are two wins shy of their record of 13, set in 2000-01.
Jesper Bratt and Nico Hischier scored for New Jersey (14-3-0). Vitek Vanecek made 25 saves to win his eighth consecutive decision.
"We are a good team, a really good team," Hischier said. "We believe in each other here and we're playing some really good hockey and it's not going to be easy playing against us.
"Definitely lots of eyes on us here (in Toronto), but we just try to focus on our game. For us, it doesn't really matter who we are playing. We try to come out with a consistent game plan, we always have, and just try to play our Devils hockey game and we've been doing that lately and that's why we have this record."
Mitchell Marner extended his point streak to 11 games, and Auston Matthews had a goal and an assist for the Maple Leafs (9-5-4), who were 5-1-1 in their previous seven games. Matt Murray made 30 saves in his second start after missing 14 games with an adductor muscle injury.
"At times it was a pretty close game, kind of back and forth," Matthews said. "We had some good possession time with the puck in the second, in the first not so much. I don't know, it was honestly a weird game to be honest. I thought especially in the third period when we were trying to push back and down a goal, we just couldn't get much going. Obviously, a big goal though to send it into overtime."