EXCLUSIVE

Jack Dylan Grazer -- otherwise known as Eddie of the Losers' Club in the "It" movie -- has a good shot at making some scary money ... in an upcoming superhero franchise.

According to Jack's contract -- obtained by TMZ -- he's going to bank at least $150k for his role as Freddy Freeman in the 2019 DC Comics film "Shazam!" ... starring Zachary Levi.

It gets better -- he can make up to $200k more in box office bonuses ... and gets a cut of the movie's merchandise cash.

But get this -- if there's a "Shazam!" sequel, Grazer's pay more than doubles to $400,000 with up to $300k in bonuses ... and his salary will DOUBLE for every additional installment of the film franchise after that.