Paracetamol (PCT) frequently contaminates natural water sources, posing potential risks to both human health and ecosystems. This study presents a computational investigation into the sensing capabilities of methylene-bridged [n]cycloparaphenylene ([n]MCPP, where n= 6, 8, and 10) nanorings for the detection of paracetamol using density functional theory (DFT) calculations. It was found that the stability of PCT@[n]MCPP complexes increases with the size of the [n]MCPP nanorings. The energy gap of the [n]MCPP nanorings is significantly influenced by the presence of the PCT drug, with the most substantial change (-44.79%) observed for the PCT@