Continuity mistake: When 1985-Jen encounters her old self, 2015-Jen walks several steps further. When the angle changes, old-Jen has stepped back 4 meters to allow for both to stare at each other closely.
Continuity mistake: When 2015-Lorraine takes the pizza out of the oven, the amount of green peppers decreases between shots. (00:33:22)
Continuity mistake: When Jen finds out that she got married in the chapel of love, her hair swaps from perfectly brushed to totally messed-up between shots.
Revealing mistake: Doc and Marty hide in the alleyway while the flying police car takes 1985-Jen home. Problem is, Doc stares in awe at the sky before the police car is in view.
Continuity mistake: After Jen is taken to her home in the future, Marty and Doc are in the car. Doc places his left hand over his glasses, but when the shot changes he's got his pinky finger raised.
Other mistake: Griff enters Cafe 80s and tells Grandpa to wax the car. Grandpa stands up and walks to the door, but Griff keeps looking at where he was standing before. This was due to the VistaGlide system of filming an empty space without stunts that could serve as cues as to where to look at.
Continuity mistake: When Marty reads the paper with the news about his son's arrest, the way he holds the paper differs between shots. (00:09:44)
Continuity mistake: At the beginning of the movie when Doc smashes through the trash cans, his glasses are not on. In the shot where he steps out of the car they are.
Suggested correction: He put them on in between shots.
Continuity mistake: During the beginning of the chase sequence, Marty is hanging on to a rope and there is a rear facing shot looking at him. There are two wet tire tracks in the shot. These disappear in the following shots.
Continuity mistake: At the start of the movie Biff is waxing George's car in the driveway with his truck parked next to it. However it completely disappears and isn't seen again even though Doc appears and parks where Biff's truck was, and Biff doesn't leave the premises.
Continuity mistake: When Marty is on Strickland's porch with the shotgun pointed at him, his hands go from in the air to down by his waist in a split second.
Continuity mistake: Int the courtyard chase scene when Griff and gang crash through the courthouse windows, the sun's position changes in every shot.
Continuity mistake: When Strickland is hitting Biff with the Almanac in the parking lot, the way the book is folded changes between shots.
Continuity mistake: While Marty gets to 2015 it's raining and the streets are wet, but when Griff's gang is chasing him the streets are dry.
Continuity mistake: When Marty confronts Biff in the alternate 1985 in the hot tub, the girls change positions. The blonde was on his left and the brunette was on his right. When they see Marty and scream, they move forward but there is no way they can switch that fast. (00:55:40)
Audio problem: When Marty is watching himself talk to Lorraine after playing Johnny B. Goode, you can see and hear Lorraine, "I hope you don't mind but George asked me if he could take me home" but watch her lips and listen. It's way out of sync.
Audio problem: When Marty follows Biff into the dance hall trying to get the sports almanac, right after he uses his binoculars he exits the dance hall. If you listen carefully to the music, the music plays uninterrupted, when given the jump in scene it should skip to a further point in the song.
