Analyzing digital images containing fibrillar structures is important across many science domains, from cytoskeleton detection in biology to filament detection in materials science. This paper introduces FibriPy, a software tool that enables accurate fiber detection from 3D imagery. We provide examples using microcomputed tomography (μ-CT), an imaging technique used for inspection of new materials samples. Our results show that FibriPy can be used for quality control of materials in the manufacturing processes.