According to the United States Census Bureau, De Kalb has a total area of 3.3 square miles (8.6 km2), of which 0.01 square miles (0.02 km2), or 0.22%, are water.[4]
As of the 2020 United States Census, there were 877 people, 480 households, and 292 families residing in the town.
2000 census
As of the census[8] of 2000, there were 972 people, 388 households, and 233 families residing in the town. The population density was 293.5 inhabitants per square mile (113.3/km2). There were 444 housing units at an average density of 134.1 per square mile (51.8/km2). The racial makeup of the town was 70.31% African American, 18.56% White, 0.21% Native American, and 0.93% from two or more races. Hispanic or Latino of any race were 0.93% of the population.
There were 388 households, out of which 26.5% had children under the age of 18 living with them, 35.8% were married couples living together, 20.9% had a female householder with no husband present, and 39.7% were non-families. 37.6% of all households were made up of individuals, and 20.9% had someone living alone who was 65 years of age or older. The average household size was 2.28 and the average family size was 3.03.
In the town, the population was spread out, with 22.6% under the age of 18, 9.0% from 18 to 24, 23.0% from 25 to 44, 19.5% from 45 to 64, and 25.8% who were 65 years of age or older. The median age was 42 years. For every 100 females, there were 83.7 males. For every 100 females age 18 and over, there were 73.3 males.
The median income for a household in the town was $21,000, and the median income for a family was $24,886. Males had a median income of $26,477 versus $16,964 for females. The per capita income for the town was $11,171. About 23.3% of families and 28.1% of the population were below the poverty line, including 38.9% of those under age 18 and 21.0% of those age 65 or over.