It was incorporated as a township by an Act of the New Jersey Legislature on February 28, 1860, from portions of both Monroe Township and North Brunswick Township. Portions of the township were taken to form Washington town within the township , Helmetta , Milltown and Spotswood .
Based on the results of the 2000 Census, New Jersey's center of population is located on Milltown Road in East Brunswick.
As of the census of 2000, there were 46,756 people, 16,372 households, and 13,081 families residing in the township. The population density was 822.4/km² (2,129.7/mi²). There were 16,640 housing units at an average density of 292.7/km² (758.0/mi²). The racial makeup of the township was 77.56% White, 2.83% Black or African American, 0.09% Native American, 16.27% Asian, 0.01% Pacific Islander, 1.12% from other races, and 2.12% from two or more races. 4.19% of the population were Hispanic or Latino of any race.
Ancestries include Italian (15.0%), Irish (13.8%), Polish (11.5%), German (10.6%), Russian (7.8%), United States (4.2%).
English is spoken by 71.25% of the township. The most common languages spoken other than English are Chinese (5.22%), Spanish (3.7%), Russian (3.14%), and Arabic (2.5%).
Of the 16,372 households, 40.5% included children under the age of 18, 68.6% were married couples living together, 8.5% had a female householder with no husband present, and 20.1% were non-families. 17.2% of all households were made up of individuals and 7.0% had someone living alone who was 65 years of age or older. The average household size was 2.84 and the average family size was 3.23.
In the township the population was spread out with 26.0% under the age of 18, 6.2% from 18 to 24, 29.3% from 25 to 44, 26.9% from 45 to 64, and 11.6% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 94.3 males. For every 100 females age 18 and over, there were 90.1 males.
The median income for a household in the township was $75,956 in 2000, with a 2005 estimate of $84,200, and the median income for a family was $86,863. Males had a median income of $60,790 versus $38,534 for females. The per capita income for the township was $33,286. 2.8% of the population and 2.1% of families were below the poverty line, including 3.1% of those under age 18 and 5.4% of those age 65 or over.
The median price of a home is $419,500.
Route 18 passes through East Brunswick, and is an important artery connecting not only to New Brunswick/U.S. Route 1 to the Jersey Shore, but also to the New Jersey Turnpike (which also passes through the township). Route 18 connects with Exit 9 of the Turnpike around mile marker 83.43. Currently, there are 15 lanes at the 9 toll gate. The Turnpike's Joyce Kilmer service area is located between Interchanges 8A and 9 northbound at milepost 78.7.
At the present time, there are plans to widen the Turnpike between Exit 9 in East Brunswick Township to Exit 8A in Monroe Township. This would change the turnpike's dual-dual configuration to "3-3-3-3" (as opposed to 2-3-3-2). East Brunswick currently houses the section of the turnpike where an extra lane in the outer truck lanes begins/merges (which is located south of Exit 9).
East Brunswick is 25.5 miles (41.0 km) from Newark Liberty International Airport in Newark / Elizabeth, via the New Jersey Turnpike. John F. Kennedy International Airport in Queens is 51.1 miles (82.2 km) away, traveling via the Belt Parkway after crossing through Staten Island.
New Jersey Transit bus service is provided on the 134 and 138 routes to the Port Authority Bus Terminal in Midtown Manhattan, on the 68 to Jersey City, and on the 811, 815 and 818 local routes.