This video demonstrates how to estimate the soil volumetric water content for a given soil matric potential based on the Campbell soil water retention function. This video was produced by Mark Barbadillo, a student in the class "Soil, Water, and Weather" at Oklahoma State University. The free etextbook used in the class, "Rain or shine: An introduction to soil physical properties and processes" by Tyson E. Ochsner, is available at https://osf.io/z4rbt/.