In this study, the authors used an online survey to investigate the perception of noise pollution by the citizens of Szombathely in Hungary. The datasets were compared to field measurements taken with a sound-level meter, and a smartphone using a free noisemeasurement app. On the whole, the participants identified the main roads and transport hubs as the most polluted areas, and parks and green spaces as the least polluted ones. Our measurements confirm that citizens are well aware of noise pollution in the city, although in some cases we found slight differences between their subjective perceptions and the actuality.