The Woolworth Building is an early American skyscraper designed by architect Cass Gilbert located at 233 Broadway in the Tribeca neighborhood of Manhattan in New York City. It was the tallest building in the world from 1913 to 1930, with a height of 792 feet (241 m). More than a century after its construction, it remains one of the 100 tallest buildings in the United States.

The Woolworth Building is bounded by Broadway and City Hall Park to its east, Park Place to its north, and Barclay Street to its south. It consists of a 30-story base topped by a 30-story tower. Its facade is mostly decorated with architectural terracotta, though the lower portions are limestone, and it features thousands of windows. The ornate lobby contains various sculptures, mosaics, and architectural touches. The structure was designed with several amenities and attractions, including a now-closed observatory on the 57th floor and a private swimming pool in the basement.

F. W. Woolworth, the founder of a brand of popular five-and-ten-cent stores, conceived the skyscraper as a headquarters for his company. Woolworth planned the skyscraper jointly with the Irving National Exchange Bank, which also agreed to use the structure as its headquarters. The Woolworth Building had originally been planned as a 12- to 16-story commercial building but underwent several revisions during its planning process. Its final height was not decided upon until January 1911. Construction started in 1910 and was completed two years later. The building officially opened on April 24, 1913.

The Woolworth Building has undergone several changes throughout its history. The facade was cleaned in 1932, and the building received an extensive renovation between 1977 and 1981. The Irving National Exchange Bank moved its headquarters to 1 Wall Street in 1931, but the Woolworth Company (later Venator Group) continued to own the Woolworth Building for most of the 20th century. The structure was sold to the Witkoff Group in 1998. The top 30 floors were sold to a developer in 2012 and converted into residences. Office and commercial tenants use the rest of the building. The Woolworth Building has been a National Historic Landmark since 1966, and a New York City designated landmark since 1983.