Boulder is a city in Boulder County, Colorado, United States. As of the 2000 census, the city had a total population of 94,673.

It is home to the University of Colorado at Boulder, the largest university in Colorado. Boulder's elevation is 5,430 feet (1,655 meters) and it is 25 miles (40 km) northwest of Denver.

Boulder has the eighth greatest population among Colorado's cities and is the largest city and county seat of Boulder County.