The director and writer of the film, Damien Chazelle, could not get funding for the movie, so he instead turned it into a short film and submitted it into the Sundance Film Festival in 2013. The short film ended up winning the Short Film Jury Award, and he got funding soon after.
Miles Teller, who has played the drums since he was 15, received blisters on his hands due to the vigorous, unconventional style of jazz drumming. Some of his blood was on the drumsticks and the drum set as a result.
For the slapping scene, J.K. Simmons and Miles Teller filmed several takes with Simmons only miming the slap. For the final take, Simmons and Teller decided to film the scene with a real, genuine slap. This is the take that is in the film.
In the scene where J.K. Simmons yells "I will fuck you like a pig," you may notice that the camera cuts away from him when he delivers that line. The line was actually taken from the short film; the original line was "I am going to gut you like a fucking pig." Damien Chazelle thought the new line was hilarious and included it in the production script. Simmons thought it was ridiculous and refused to say that line, but Chazelle included the 'mistake' in post-production anyway.
Early in the film, Andrew listens to a CD of Buddy Rich. Buddy Rich was a drummer infamous for his short temper, and he would regularly berate and verbally abuse his band mates for what he considered inferior musicianship; this foreshadows Fletcher's abusive treatment of his students.
Part of the film is based on director/writer Damien Chazelle's experience as a band student in high school. In a Q&A after a screening, Chazelle stated he was intimidated by his band instructor's presence.
On his date with Nicole, a song comes on in the background that Andrew recognizes as by Jackie Hill from 1938. There is no such jazz artist named Jackie Hill. That song, along with many of the compositions featured in the film, are the works of the film's composer Justin Hurwitz.
The chart "Whiplash" performed in the film is of the type referred to by jazz players as a "time chart" - a piece with an unconventional time signature (in this case, 14/8). The chart's arranger - Hank Levy - is famous within jazz circles for his numerous "time chart" classics.
Damien Chazelle wanted Miles Teller for the role of Andrew Neiman when he was filming the original short film Whiplash (2013) but Teller was unavailable so Johnny Simmons was cast instead. When casting the feature film version, the finalists for the role were Teller and Simmons. Teller was cast because he was a better known name and an actual drummer.
J.K. Simmons was up against Ethan Hawke (for Boyhood (2014)) at the Academy Awards for Best Actor in a Supporting Role. Hawke played his character on and off, occasionally, over the course of 12 years. Simmons played his for 19 days (not including the days playing the same character in the short film of the same name).
J.K. Simmons actually had his own musical background. His mother was a middle-school music teacher, and his father was director of the music department at the University of Montana, where J.K. himself earned a music degree.
To receive funding, writer/director Damien Chazelle filmed a large chunk of the screenplay and submitted it into festivals as a short. J.K. Simmons was cast as the same character whereas Andrew is played by Johnny Simmons. (No relation).
There are two theories on how Charlie "Yardbird" Parker actually got his name. 1) He lived "free as a bird". Or the more commonly accepted one, 2) When touring with Jay McShann, they accidentally hit a chicken (a yardbird) with their car and Parker made them stop to pick it up so he could have his landlady cook it for him.
Fletcher asks the Nassau band Bassist to play "5 bars of Donna Lee", Donna Lee being a jazz standard by Charlie Parker, renown to bass players because of the version played by Jaco Pastorius with bass playing the main theme. The band Bassist plays a regular walking bass line though.
Jason Reitman convinced Damien Chazelle to cut a scene involving Fletcher sitting alone in his apartment after Andrew's first "Studio Band" class. This due to the fact the film is all from Andrew's perspective and scenes without him will detract the tone of the film.
When asked about the film's ending J.K. Simmons claimed that he and writer-director Damien Chazelle wanted "to inspire discussion and debate and not decide - are we happy for Andrew Neimann or are we lamenting his loss of humanity. The debate I love, is how far is too far? How much is too much? Is it worth it? This kind of relentless abuse might be necessary and appropriate if you're training Navy Seals, but I don't know if it's appropriate in a music school. But it's there, and it can be productive; there's no denying that. From my own perspective, I'd rather have a pretty girlfriend than go work with this guy and have my hands bleed all the time. I would have made a different choice."
In an interview with Screen Crush, Damien Chazelle stated the ending implied Andrew's future would be like Charlie Parker, where he would rather die drunk and broke at the age of 34. This was earlier remarked in the heated conversation during the family dinner scene. Chazelle also mentioned that he deliberately ended the film without any scene between Andrew and Fletcher after the performance, as he believes their competitive relationship to be unresolved.
The studio originally gave Damien Chazelle a note saying "He's good at drumming, we get it" in an attempt to try and take out the ending drum solo. Chazelle disagreed and kept the drum solo in the film.
The title of the film refers to many things: the first complex jazz piece Andrew learned and performed with Fletcher's band, a common neck injury from car accidents, one of which was depicted during the film, the beating of a drum similar to the cracking or lashing of a whip, and, of course, the abuse he suffers under Fletcher.
It is absurd to think that a drummer in a prestigious music school couldn't play the tempo that the conductor started out with. A drummer like that would never get into that kind of school in the first place. That is very basic skills.