| | Trenton, TN | McKenzie, TN | United States |
| Population | 4,277 | 5,590 | 329,725,481 |
| Female Population | 49.2% | 50.5% | 50.5% |
| Male Population | 50.9% | 49.6% | 49.5% |
| Median Age | 34.7 | 37.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 4,287 | 5,261 | 309,327,143 |
| Population - 2000 | 4,683 | 5,295 | 285,036,114 |
| Population - 1990 | 4,836 | 5,168 | 251,960,433 |
| Pop. 2000 to Now | -11.5% | 0.2% | 15.6% |
| Pop. 1990 to Now | -14.3% | 2.6% | 30.8% |
| space4 | | | |
| Population Density | 532.6 | 884.5 | 93.4 |
| Land Area | 8.0 | 6.3 | 3,531,905.4 |
| Water Area | 0.1 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Trenton, TN | McKenzie, TN | United States |
| Age 0 to 4 | 8.4% | 6.0% | 5.9% |
| Age 5 to 9 | 6.5% | 5.0% | 6.1% |
| Age 10 to 14 | 4.5% | 4.7% | 6.6% |
| Age 15 to 17 | 2.2% | 4.3% | 3.9% |
| Age 18 to 20 | 4.4% | 10.8% | 4.0% |
| Age 21 to 24 | 4.8% | 4.7% | 5.2% |
| Age 25 to 34 | 19.4% | 11.9% | 13.8% |
| Age 35 to 44 | 7.1% | 9.1% | 12.9% |
| Age 45 to 54 | 15.8% | 11.2% | 12.6% |
| Age 55 to 59 | 5.8% | 7.5% | 6.7% |
| Age 60 to 64 | 5.0% | 4.8% | 6.3% |
| Age 65 to 74 | 7.4% | 11.1% | 9.6% |
| Age 75 to 84 | 6.3% | 6.1% | 4.5% |
| Age 85 and over | 2.4% | 2.7% | 1.9% |
| space1 | | | |
| Race | | | |
| | Trenton, TN | McKenzie, TN | United States |
| White | 55.0% | 78.5% | 59.4% |
| Black | 29.9% | 15.4% | 12.2% |
| Asian | 0.0% | 1.9% | 5.6% |
| Native American | 0.1% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.2% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 10.1% | 0.6% | 3.2% |
| Hispanic | 4.9% | 3.4% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Trenton, TN | McKenzie, TN | United States |
| Married Population | 35.6% | 42.4% | 49.8% |
| Currently Married | 31.3% | 40.8% | 48.0% |
| Married but Separated | 4.3% | 1.6% | 1.8% |
| Single Population | 64.4% | 57.6% | 50.2% |
| Never Married | 40.1% | 37.4% | 33.8% |
| Divorced | 16.4% | 12.3% | 10.8% |
| Widowed | 7.9% | 7.9% | 5.6% |
| space5 | | | |
| Household Size | 2.37 | 2.53 | 2.60 |
| Households | 1,603 | 1,986 | 124,010,992 |
| Family Households | 854 | 1,256 | 80,755,759 |
| Married couple, w/children | 16.6% | 29.5% | 30.5% |
| Married couple, no children | 39.7% | 43.7% | 42.9% |
| Non Family Households | 749 | 730 | 43,255,233 |
| Single householder, w/children | 30.8% | 16.2% | 15.8% |
| Single householder, no children | 12.9% | 10.6% | 10.8% |