Harper, IA has a population of 96 and is the 27,047th largest city in the United States. The population density is 1,081 per sq mi which is 1878% higher than the Iowa average and 1093% higher than the national average. The median age in Harper is 35 which is approximately 9% lower than the Iowa average of 38. In Harper, 63% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 92% of Harper residents were born in Iowa, 8% were born out of state, 0% were born outside of the United States and 0% were foreign born.