Popsugar Family Autism What Is Autism? 11 Things You Need to Know About Autism Today April 2, 2014 by Rebecca Gruber View On One Page Photo 4 of 11 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 4 When Children Are Typically Diagnosed While a reliable autism diagnosis can be given as early as 2 years old, on average, children are diagnosed at 4 years old. Source: Flickr user CIA DE FOTO Previous Next Start Slideshow AutismChild Health And Safety