Recent advances in high-throughput laboratory technologies and bioinformatics tools are redefining how we view inflammatory bowel disease (IBD). Instead of 2 diseases, we now see a diverse set of molecular subtypes. Large-scale investigation of the genome, exome, transcriptome, proteome, metabolome, microbiome, and epigenome are providing transformative insights into the pathophysiology of IBD, with the promise of accurately predicting prognosis and targeting therapy. Understanding these tools and their application is crucial to navigating the molecular era of IBD. This review aims to help the IBD clinician understand, appreciate, and eventually incorporate this coming paradigm shift to improve the care of children with IBD.