| | Allen, KY | Fort Mitchell, KY | United States |
| Population | 213 | 8,618 | 329,725,481 |
| Female Population | 56.3% | 48.7% | 50.5% |
| Male Population | 43.7% | 51.3% | 49.5% |
| Median Age | 20.3 | 34.6 | 38.4 |
| space3 | | | |
| Population - 2010 | 193 | 8,167 | 309,327,143 |
| Population - 2000 | 150 | 8,089 | 285,036,114 |
| Population - 1990 | 229 | 7,438 | 251,960,433 |
| Pop. 2000 to Now | 12.0% | 2.2% | 15.6% |
| Pop. 1990 to Now | -26.6% | 11.1% | 30.8% |
| space4 | | | |
| Population Density | 1,189.9 | 2,783.6 | 93.4 |
| Land Area | 0.2 | 3.1 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Allen, KY | Fort Mitchell, KY | United States |
| Age 0 to 4 | 23.9% | 6.3% | 5.9% |
| Age 5 to 9 | 4.7% | 7.9% | 6.1% |
| Age 10 to 14 | 10.3% | 7.8% | 6.6% |
| Age 15 to 17 | 10.8% | 6.3% | 3.9% |
| Age 18 to 20 | 0.9% | 5.3% | 4.0% |
| Age 21 to 24 | 5.6% | 4.5% | 5.2% |
| Age 25 to 34 | 7.0% | 12.4% | 13.8% |
| Age 35 to 44 | 23.9% | 16.2% | 12.9% |
| Age 45 to 54 | 5.6% | 11.3% | 12.6% |
| Age 55 to 59 | 0.0% | 6.1% | 6.7% |
| Age 60 to 64 | 0.9% | 5.5% | 6.3% |
| Age 65 to 74 | 1.9% | 5.3% | 9.6% |
| Age 75 to 84 | 4.2% | 3.9% | 4.5% |
| Age 85 and over | 0.0% | 1.3% | 1.9% |
| space1 | | | |
| Race | | | |
| | Allen, KY | Fort Mitchell, KY | United States |
| White | 93.0% | 94.7% | 59.4% |
| Black | 0.0% | 0.9% | 12.2% |
| Asian | 2.3% | 0.5% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 4.7% | 1.8% | 3.2% |
| Hispanic | 0.0% | 2.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Allen, KY | Fort Mitchell, KY | United States |
| Married Population | 28.5% | 46.4% | 49.8% |
| Currently Married | 26.9% | 46.1% | 48.0% |
| Married but Separated | 1.5% | 0.3% | 1.8% |
| Single Population | 71.5% | 53.6% | 50.2% |
| Never Married | 37.7% | 34.7% | 33.8% |
| Divorced | 22.3% | 15.5% | 10.8% |
| Widowed | 11.5% | 3.5% | 5.6% |
| space5 | | | |
| Household Size | 3.13 | 2.47 | 2.60 |
| Households | 68 | 3,467 | 124,010,992 |
| Family Households | 30 | 2,079 | 80,755,759 |
| Married couple, w/children | 40.0% | 38.5% | 30.5% |
| Married couple, no children | 10.0% | 35.3% | 42.9% |
| Non Family Households | 38 | 1,388 | 43,255,233 |
| Single householder, w/children | 36.7% | 16.9% | 15.8% |
| Single householder, no children | 13.3% | 9.3% | 10.8% |