Sewaren, NJ has a population of 2,405 and is the 10,050th largest city in the United States. The population density is 2,535 per sq mi which is 253419% higher than the New Jersey average and 2698% higher than the national average. The median age in Sewaren is 41 which is approximately 3% higher than the New Jersey average of 40. In Sewaren, 53% of the population over 15 years of age are married, 75% speak English and 10% speak Spanish. 67% of Sewaren residents were born in New Jersey, 13% were born out of state, 3% were born outside of the United States and 17% were foreign born.