The Ironbound is a neighborhood in the city of Newark in Essex County, in the U.S. state of New Jersey. It is a large working-class multi-ethnic community, covering about 4 square miles (10 km2). Historically, the area was called "Dutch Neck," "Down Neck," or simply "the Neck," for its location by a bend of the Passaic River. Part of Newark's East Ward, the Ironbound is directly east of Newark Penn Station and Downtown Newark, and south and west of the river. The neighborhood is connected by the Jackson Street Bridge over the river to Harrison and Kearny.

Newark is the most populous city in the U.S. state of New Jersey, the seat of Essex County, and a principal city of the New York metropolitan area. As of the 2020 census, the city's population was 311,549. The Population Estimates Program calculated a population of 305,344 for 2022, making it the 66th-most populous municipality in the nation.