| | Jamestown, CO | Idaho Springs, CO | United States |
| Population | 281 | 2,044 | 329,725,481 |
| Female Population | 50.2% | 54.4% | 50.5% |
| Male Population | 49.8% | 45.6% | 49.5% |
| Median Age | 46.6 | 40.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 274 | 1,724 | 309,327,143 |
| Population - 2000 | 205 | 1,889 | 285,036,114 |
| Population - 1990 | 251 | 1,834 | 251,960,433 |
| Pop. 2000 to Now | 23.9% | -1.7% | 15.6% |
| Pop. 1990 to Now | 1.2% | 1.3% | 30.8% |
| space4 | | | |
| Population Density | 451.0 | 908.4 | 93.4 |
| Land Area | 0.6 | 2.3 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Jamestown, CO | Idaho Springs, CO | United States |
| Age 0 to 4 | 0.0% | 2.6% | 5.9% |
| Age 5 to 9 | 4.3% | 3.6% | 6.1% |
| Age 10 to 14 | 3.2% | 0.6% | 6.6% |
| Age 15 to 17 | 5.3% | 1.8% | 3.9% |
| Age 18 to 20 | 0.0% | 2.6% | 4.0% |
| Age 21 to 24 | 6.1% | 13.3% | 5.2% |
| Age 25 to 34 | 18.1% | 19.8% | 13.8% |
| Age 35 to 44 | 9.6% | 10.5% | 12.9% |
| Age 45 to 54 | 15.7% | 11.2% | 12.6% |
| Age 55 to 59 | 13.2% | 7.8% | 6.7% |
| Age 60 to 64 | 10.7% | 8.5% | 6.3% |
| Age 65 to 74 | 12.5% | 13.4% | 9.6% |
| Age 75 to 84 | 1.4% | 2.8% | 4.5% |
| Age 85 and over | 0.0% | 1.7% | 1.9% |
| space1 | | | |
| Race | | | |
| | Jamestown, CO | Idaho Springs, CO | United States |
| White | 90.7% | 80.2% | 59.4% |
| Black | 0.0% | 2.8% | 12.2% |
| Asian | 0.0% | 0.0% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 1.4% | 1.3% | 0.4% |
| Two or More Races | 0.7% | 2.3% | 3.2% |
| Hispanic | 7.1% | 13.4% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Jamestown, CO | Idaho Springs, CO | United States |
| Married Population | 48.1% | 47.0% | 49.8% |
| Currently Married | 48.1% | 46.3% | 48.0% |
| Married but Separated | 0.0% | 0.6% | 1.8% |
| Single Population | 51.9% | 53.0% | 50.2% |
| Never Married | 38.5% | 34.1% | 33.8% |
| Divorced | 13.5% | 14.7% | 10.8% |
| Widowed | 0.0% | 4.2% | 5.6% |
| space5 | | | |
| Household Size | 2.34 | 2.37 | 2.60 |
| Households | 120 | 863 | 124,010,992 |
| Family Households | 72 | 499 | 80,755,759 |
| Married couple, w/children | 20.8% | 29.7% | 30.5% |
| Married couple, no children | 58.3% | 54.1% | 42.9% |
| Non Family Households | 48 | 364 | 43,255,233 |
| Single householder, w/children | 15.3% | 0.0% | 15.8% |
| Single householder, no children | 5.6% | 16.2% | 10.8% |