Doon, IA has a population of 632 and is the 18,106th largest city in the United States. The population density is 1,102 per sq mi which is 1917% higher than the Iowa average and 1117% higher than the national average. The median age in Doon is 36 which is approximately 6% lower than the Iowa average of 38. In Doon, 63% of the population over 15 years of age are married, 99% speak English and 0% speak Spanish. 74% of Doon residents were born in Iowa, 26% were born out of state, 1% were born outside of the United States and 0% were foreign born.