Summary This paper compares height, length, width, and pressure data from a laboratory experiment to predictions from a three-dimensional (3D) planar hydraulic fracture model for the case of a fracture propagating in a lower-stress payzone region bounded by two symmetric higher-stress barrier regions. A laboratory method that creates step-like stress changes on an interface between two transparent polymethylmethacrylate (PMMA) blocks is described. A fracture is propagated along this interface while measuring fracture geometry and full-field fracture width (opening) by analysis of the light intensity in images of the growing fracture. The fracture grew in overall height to 1.7 times the pay height and in half-length to 3 times the pay height. Results from a planar 3D numerical model closely matched the experimental data for overall fracture shape, length, height growth, and injection pressure. The data are presented so other numerical models can be compared with these detailed measurements.