Gibson City, IL has a population of 3,423 and is the 8,158th largest city in the United States. The population density is 1,462 per sq mi which is 558% higher than the Illinois average and 1513% higher than the national average. The median age in Gibson City is 40 which is approximately 7% higher than the Illinois average of 37. In Gibson City, 62% of the population over 15 years of age are married, 99% speak English and 0% speak Spanish. 79% of Gibson City residents were born in Illinois, 20% were born out of state, 0% were born outside of the United States and 0% were foreign born.