A digital system has been developed to measure the volume of containers, using Helmholtz resonance. It consists of an excitation device, made with recycled compact disks (CDs), that covers the normally open face of the container and provides an air duct and a neck, according to the model of a Helmholtz resonator. In a previous study (Fuks et al. DAGA 2021) this device was employed to measure the resonant properties of several hollow geometrical solids. The produced sound, by natural or artificial blowing, is analyzed by a smartphone app. The device delivers results through visual and auditory interfaces, being suitable for visually impaired users. The operational range is between 50 ml and 2000 ml, with an error below ±10%. The correction for airflow is discussed, as a function of playing frequency and flow rate, for the fixed bocal. Besides the Helmholtz formula, the system provides an alternative method, based on interpolation from an experimental lookup table. Practical, entertainment, and educational applications are considered.