Clarion, PA has a population of 5,073 and is the 6,405th largest city in the United States. The population density is 3,222 per sq mi which is 1063% higher than the Pennsylvania average and 3457% higher than the national average. The median age in Clarion is 24 which is approximately 41% lower than the Pennsylvania average of 41. In Clarion, 35% of the population over 15 years of age are married, 94% speak English and 0% speak Spanish. 76% of Clarion residents were born in Pennsylvania, 19% were born out of state, 0% were born outside of the United States and 5% were foreign born.