Monitoring disease activity in Crohn’s disease is important as achieving endoscopic remission significantly improves clinical outcomes. Fecal calprotectin is a common non-invasive biomarker for monitoring disease activity. However, fecal calprotectin does not always correlate with other disease activity assessments and stool samples can be difficult to collect and inconvenient to return. Thus, we aimed to compare the association between calprotectin levels in stool, saliva, and blood, and assess to their correlation with endoscopic and histologic outcomes among patients with Crohn’s disease.