To date, the Ultimate Edition of Batman V Superman: Dawn of Justice is easily the longest film in the current DC canon at three hours and three minutes in length, while Suicide Squad was previously the shortest DC film at two hours and seventeen minutes.
If that reported runtime from Fandango’s Erik Davis is correct, then it means Justice League will become the shortest DCEU by a fairly substantial margin.
One could naturally assume that Justice League would’ve been on the longer side because it is arguably the most densely populated DC movie yet, but now it appears that the folks behind the film have endeavored to keep it as lean and streamlined as possible.