Brookings, SD has a population of 23,292 and is the 1,869th largest city in the United States. The population density is 1,733 per sq mi which is 15929% higher than the South Dakota average and 1812% higher than the national average. The median age in Brookings is 24 which is approximately 36% lower than the South Dakota average of 37. In Brookings, 40% of the population over 15 years of age are married, 92% speak English and 2% speak Spanish. 57% of Brookings residents were born in South Dakota, 36% were born out of state, 0% were born outside of the United States and 7% were foreign born.