| | Trotwood, OH | Defiance, OH | United States |
| Population | 23,157 | 17,155 | 329,725,481 |
| Female Population | 57.6% | 51.0% | 50.5% |
| Male Population | 42.5% | 49.0% | 49.5% |
| Median Age | 44.7 | 40.4 | 38.4 |
| space3 | | | |
| Population - 2010 | 24,429 | 17,165 | 309,327,143 |
| Population - 2000 | 27,420 | 16,465 | 285,036,114 |
| Population - 1990 | 8,816 | 16,768 | 251,960,433 |
| Pop. 2000 to Now | -10.9% | 0.1% | 15.6% |
| Pop. 1990 to Now | 177.1% | -1.7% | 30.8% |
| space4 | | | |
| Population Density | 759.6 | 1,369.6 | 93.4 |
| Land Area | 30.5 | 12.5 | 3,531,905.4 |
| Water Area | 0.0 | 0.5 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Trotwood, OH | Defiance, OH | United States |
| Age 0 to 4 | 5.2% | 6.3% | 5.9% |
| Age 5 to 9 | 6.6% | 5.9% | 6.1% |
| Age 10 to 14 | 5.7% | 5.1% | 6.6% |
| Age 15 to 17 | 4.0% | 3.4% | 3.9% |
| Age 18 to 20 | 2.9% | 5.8% | 4.0% |
| Age 21 to 24 | 3.8% | 5.6% | 5.2% |
| Age 25 to 34 | 10.3% | 11.9% | 13.8% |
| Age 35 to 44 | 12.0% | 11.9% | 12.9% |
| Age 45 to 54 | 13.7% | 11.2% | 12.6% |
| Age 55 to 59 | 6.6% | 6.4% | 6.7% |
| Age 60 to 64 | 8.0% | 6.9% | 6.3% |
| Age 65 to 74 | 11.4% | 11.8% | 9.6% |
| Age 75 to 84 | 7.1% | 5.9% | 4.5% |
| Age 85 and over | 2.7% | 2.0% | 1.9% |
| space1 | | | |
| Race | | | |
| | Trotwood, OH | Defiance, OH | United States |
| White | 29.5% | 80.7% | 59.4% |
| Black | 64.5% | 2.8% | 12.2% |
| Asian | 0.2% | 0.1% | 5.6% |
| Native American | 0.0% | 0.2% | 0.6% |
| Hawaiian, Pacific Islander | 0.1% | 0.0% | 0.2% |
| Other | 0.2% | 0.0% | 0.4% |
| Two or More Races | 4.1% | 2.0% | 3.2% |
| Hispanic | 1.3% | 14.1% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Trotwood, OH | Defiance, OH | United States |
| Married Population | 33.8% | 50.4% | 49.8% |
| Currently Married | 31.1% | 47.8% | 48.0% |
| Married but Separated | 2.7% | 2.6% | 1.8% |
| Single Population | 66.2% | 49.6% | 50.2% |
| Never Married | 39.8% | 33.0% | 33.8% |
| Divorced | 17.3% | 11.4% | 10.8% |
| Widowed | 9.1% | 5.2% | 5.6% |
| space5 | | | |
| Household Size | 2.20 | 2.33 | 2.60 |
| Households | 10,212 | 7,156 | 124,010,992 |
| Family Households | 5,591 | 4,411 | 80,755,759 |
| Married couple, w/children | 14.4% | 20.9% | 30.5% |
| Married couple, no children | 35.1% | 52.5% | 42.9% |
| Non Family Households | 4,621 | 2,745 | 43,255,233 |
| Single householder, w/children | 29.1% | 20.7% | 15.8% |
| Single householder, no children | 21.4% | 5.9% | 10.8% |