Passaic is a city located in Passaic County within the state of New Jersey in the United States. It serves as one of the state's significant municipalities, ranking as the 16th-most populous city in New Jersey according to the 2020 United States census.
The city is characterized by its high population density, ranking as the fifth-most densely populated municipality in the United States among cities with more than 50,000 people. As of the 2020 census, Passaic had a population of 70,537, which represented an increase from previous decades. The city maintains a density of more than 22,000 people per square mile.