Lexington, MO has a population of 4,620 and is the 6,812th largest city in the United States. The population density is 884 per sq mi which is 923% higher than the Missouri average and 875% higher than the national average. The median age in Lexington is 46 which is approximately 21% higher than the Missouri average of 38. In Lexington, 63% of the population over 15 years of age are married, 95% speak English and 4% speak Spanish. 73% of Lexington residents were born in Missouri, 24% were born out of state, 1% were born outside of the United States and 2% were foreign born.