The definition varies, but millennials start somewhere around 1980-1984 and end around 1996-2000 depending on the source. My comment about him possibly being Gen Z doesn't really matter - there's not much difference between young millennials and old gen z'ers. I just thought it was interesting that our generation is getting so old that the next one is starting to graduate high school. Personally, I feel like millennials should be 2 different generations. There's a pretty massive difference between old and young millennials, and social media wasn't around (or nearly as big) for a lot of millennials when they went through high school. For instance, Facebook didn't open up to non-college students until late 2006, and Instagram and Snapchat weren't around until 2010-12. I mean, I'm a millennial, and I remember before internet was widely used.