Pretty accurate except for a few numbers
The actual number of participants was 24 - 12 on each side. The prison was a lot smaller, at least originally. There were 3 backups on both sides.
However, the conditions, wardrobes, and treatment of the prisoners in this film are well-documented and accurate. The kid leaving and demanding an attorney is accurate.
The experiment was moved to a different section of Stanford after that.
The prisoner-on-prisoner harassment happened. The numbers-not-names happened. The experiment was stopped because of the girlfriend.
I appreciate a more factual film than either of "The/Das Experiment."
Lastly, the DOJ, military, and EU Commission on Human Rights adapted this into their treatment of prisoners.
"I do not like mixing up moralities and mathematics."
Churchill