Clarkson Valley, MO has a population of 2,638 and is the 9,499th largest city in the United States. The population density is 978 per sq mi which is 1032% higher than the Missouri average and 979% higher than the national average. The median age in Clarkson Valley is 49 which is approximately 29% higher than the Missouri average of 38. In Clarkson Valley, 80% of the population over 15 years of age are married, 91% speak English and 2% speak Spanish. 51% of Clarkson Valley residents were born in Missouri, 39% were born out of state, 2% were born outside of the United States and 8% were foreign born.