AreaVibes reveals the best places to live in Colorado for 2016 using our Livability Score. The Livability Score for each city in Colorado is calculated out of 100 from a unique algorithm based on various metrics, including: amenities, cost of living, crime, education, employment, housing and weather. Colorado has a population of 5,197,580 and a population density of 49.8 people per square mile. The capital city is Denver and the largest city in Colorado is Denver. To filter the results, use the dropdown options to sort by population or category.