Gray Summit, MO has a population of 2,977 and is the 8,862nd largest city in the United States. The population density is 404 per sq mi which is 367% higher than the Missouri average and 346% higher than the national average. The median age in Gray Summit is 33 which is approximately 14% lower than the Missouri average of 38. In Gray Summit, 66% of the population over 15 years of age are married, 98% speak English and 2% speak Spanish. 81% of Gray Summit residents were born in Missouri, 17% were born out of state, 1% were born outside of the United States and 2% were foreign born.