Clarence, IA has a population of 976 and is the 15,314th largest city in the United States. The population density is 1,444 per sq mi which is 2543% higher than the Iowa average and 1494% higher than the national average. The median age in Clarence is 49 which is approximately 29% higher than the Iowa average of 38. In Clarence, 58% of the population over 15 years of age are married, 94% speak English and 2% speak Spanish. 82% of Clarence residents were born in Iowa, 18% were born out of state, 0% were born outside of the United States and 0% were foreign born.