As of the census of 2000, there were 66,715 people, 17,175 households, and 13,533 families residing in the city of Jacksonville. The population density was 1,500.0 people per square mile (579.1/km²). There were 18,312 housing units at an average density of 411.7 per square mile (159.0/km²). The racial composition of the city was: 63.94% White, 23.96% Black or African American, 10.05% Hispanic or Latino American, 2.07% Asian American, 0.75% Native American, 0.19% Native Hawaiian or Other Pacific Islander, 5.42% some other race, and 3.67% two or more races. As of 2009, the estimated population for the city was 80,542.
There were 17,175 households out of which 49.5% had children under the age of 18 living with them, 63.8% were married couples living together, 12.3% had a female householder with no husband present, and 21.2% were non-families. 16.6% of all households were made up of individuals and 5.1% had someone living alone who was 65 years of age or older. The average household size was 2.83 and the average family size was 3.8
In Jacksonville the population was spread out with 24.3% under the age of 18, 36.3% from 18 to 24, 25.9% from 25 to 44, 8.8% from 45 to 64, and 4.8% who were 65 years of age or older. The median age was 22 years. Jacksonville has been named the youngest city in the nation (lowest median age) on various lists. For every 100 females, there were 156.2 males. For every 100 females age 18 and over, there were 178.6 males.
The median income for a household in the city was $32,544, and the median income for a family was $33,763. Males had a median income of $17,121 versus $19,931 for females. The per capita income for the city was $14,237. About 12.5% of families and 14.1% of the population were below the poverty line, including 18.0% of those under age 18 and 17.7% of those age 65 or over.
The 2013 population estimate was 69,079, with 67.7% identifying as White and 20.0% identifying as Black or African-American. The median household income for 2009-2013 was $42,459.