Superior, CO has a population of 12,928 and is the 3,224th largest city in the United States. The population density is 3,236 per sq mi which is 6400% higher than the Colorado average and 3472% higher than the national average. The median age in Superior is 33 which is approximately 8% lower than the Colorado average of 36. In Superior, 60% of the population over 15 years of age are married, 76% speak English and 3% speak Spanish. 31% of Superior residents were born in Colorado, 48% were born out of state, 1% were born outside of the United States and 20% were foreign born.