Boone, IA has a population of 12,609 and is the 3,288th largest city in the United States. The population density is 1,394 per sq mi which is 2451% higher than the Iowa average and 1438% higher than the national average. The median age in Boone is 38 which is approximately 1% higher than the Iowa average of 38. In Boone, 61% of the population over 15 years of age are married, 97% speak English and 2% speak Spanish. 77% of Boone residents were born in Iowa, 21% were born out of state, 0% were born outside of the United States and 1% were foreign born.