[4] Danbury is located northeast of the center of Brazoria County, next to Flores Bayou.

According to the United States Census Bureau, Danbury has a total area of 0.97 square miles (2.5 km2), all land.

[4] In 2006, the average elevation was 21.4 feet (6.5 m) above mean sea level (MSL), which reflects a 0.168-inch (4.3 mm) negative deviation compared to a 1998 study.

This decrease is believed to be caused by the extraction of groundwater (9% of total declination), the extraction of petroleum products (88% of total declination) with a probable calculated seasonal difference in soil moisture accounting for the remainder.

[citation needed] As of the 2020 United States census, there were 1,671 people, 467 households, and 355 families residing in the city.

Danbury is served by three churches (two Baptist and one Catholic) which claim as members 44% of the city's population.

The Texas Legislature designated Danbury ISD as being in the Alvin Community College zone.