Factual error: In the disturbing assault scene, after having his head smashed into a mirror and banged against the sink multiple times, there is no way Tyler would be conscious for the rest of the scene.
Continuity mistake: When Hannah makes the list with names involving her past events, they differ substantially between the close-up when they're written and the final wide angle once the paper is finished. Check Alexander: first an irregular oval with a straight side, then a perfect oval.
Hannah: I'm glad you're still listening. Having fun?
More trivia for 13 Reasons Why