Abstract This work aims to develop a fast, cheap, and easy-to-use sensor for paracetamol detection. Non-enzymatic electrochemical sensing was selected because of the electrochemical activity of paracetamol and the easy and cheap way of sensing it using the commercially available Screen-printed carbon electrodes (SPCEs). In order to improve the sensing, five concentrations of zinc ferrite (ZnxFe1−xO4, x from 0.2 to 1) nanoparticles, five concentrations of nickel ferrite (NixFe1−xO4, x from 0.2 to 1) nanoparticles, and magnetite nanoparticles were synthesized using an auto-precipitation method followed by a hydrothermal synthesis. Nanoparticles act as catalytic agents, improving the electron transfer rate and, therefore, the sensitivity and the limit of detection (LOD).