Brass Castle, NJ has a population of 1,608 and is the 12,304th largest city in the United States. The population density is 548 per sq mi which is 54659% higher than the New Jersey average and 504% higher than the national average. The median age in Brass Castle is 44 which is approximately 10% higher than the New Jersey average of 40. In Brass Castle, 73% of the population over 15 years of age are married, 94% speak English and 0% speak Spanish. 60% of Brass Castle residents were born in New Jersey, 31% were born out of state, 2% were born outside of the United States and 8% were foreign born.