Gainesville, TX has a population of 16,169 and is the 2,651st largest city in the United States. The population density is 838 per sq mi which is 764% higher than the Texas average and 825% higher than the national average. The median age in Gainesville is 34 which is approximately equal to the Texas average of 34. In Gainesville, 57% of the population over 15 years of age are married, 73% speak English and 24% speak Spanish. 63% of Gainesville residents were born in Texas, 22% were born out of state, 0% were born outside of the United States and 14% were foreign born.