According to the United States Census Bureau, the CDP had a total area of 3.190 square miles, including 3.189 square miles of land and 0.001 square miles of water.
Iselin's downtown is centered on Oak Tree Road, bound by the Garden State Parkway to the West, and Route 27 to the East. Once home to a wide array of shops, eateries, services, and complemented by a single-screen 1920s movie palace, the area was in obvious decline in the 1980s. An influx of Asian Indian immigration beginning in the early 1990s led to the area's revitalization. Formerly vacant stores were tenanted, and additional retail spaces built as the area became known for its high quality Indian food, sweets, clothing, jewelry, music, and other goods.
Iselin hosts one of the region's main centers of Indian American cultural diversity. The growing Little India is a South Asian-focused commercial strip in Middlesex County, the U.S. county with the highest concentration of Asian Indians. The Oak Tree Road strip runs for about one-and-a-half miles through Iselin and neighboring Edison Township,near the area's sprawling Chinatown and Koreatown, running along New Jersey Route 27. The zone is the largest and most diverse South Asian cultural hub in the United States. In Middlesex County, election ballots are printed in English, Spanish, Gujarati, Hindi, and Punjabi. According to the 2017 American Community Survey, 42.6% of Iselin residents identified themselves as being Indian American, the highest percentage for any census-designated place in the United States.
2010 Census
2000 Census
As of the 2000 United States Census there were 16,698 people, 6,007 households, and 4,511 families residing in the CDP. The population density was 2,059.8/km2. There were 6,137 housing units at an average density of 757.0/km2. The racial makeup of the CDP was 64.65% White, 6.02% African American, 0.12% Native American, 25.16% Asian, 0.01% Pacific Islander, 1.75% from other races, and 2.28% from two or more races. Hispanic or Latino of any race were 5.47% of the population. There were 6,007 households, out of which 32.0% had children under the age of 18 living with them, 61.5% were married couples living together, 9.8% had a female householder with no husband present, and 24.9% were non-families. 20.8% of all households were made up of individuals, and 8.6% had someone living alone who was 65 years of age or older. The average household size was 2.78 and the average family size was 3.24. In the CDP the population was spread out, with 21.8% under the age of 18, 7.6% from 18 to 24, 33.9% from 25 to 44, 22.7% from 45 to 64, and 14.0% who were 65 years of age or older. The median age was 37 years. For every 100 females, there were 96.8 males. For every 100 females age 18 and over, there were 95.1 males. The median income for a household in the CDP was $65,424, and the median income for a family was $71,913. Males had a median income of $50,145 versus $36,131 for females. The per capita income for the CDP was $26,793. About 1.9% of families and 3.2% of the population were below the poverty line, including 2.8% of those under age 18 and 4.9% of those age 65 or over.
Notable people
People who were born in, residents of, or otherwise closely associated with Iselin include:
Tom DeSanto, film producer and screenwriter best known for his work with long-time friend Bryan Singer, especially with his contributions to the first two X-Men movies.
James Swann, serial killer whose random drive-by shotgun shootings in Washington, D.C. in 1993 earned him the nickname "The Shotgun Stalker" in the press.