Trogen has a population () of 1,688, of which about 7.7% are foreign nationals. Over the last 10 years the population has decreased at a rate of -15.2%. Most of the population () speaks German (92.9%), with Serbo-Croatian being second most common ( 2.0%) and Italian being third ( 0.9%). , the gender distribution of the population was 50.3% male and 49.7% female. The age distribution, , in Trogen is; 130 people or 7.0% of the population are between 0–6 years old. 271 people or 14.5% are 6-15, and 149 people or 8.0% are 16-19. Of the adult population, 80 people or 4.3% of the population are between 20–24 years old. 502 people or 26.9% are 25-44, and 452 people or 24.2% are 45-64. The senior population distribution is 186 people or 10.0% of the population are between 65–79 years old, and 97 people or 5.2% are over 80.