| | Ontario, OH | Fox Lake, IL | United States |
| Population | 6,596 | 10,945 | 329,725,481 |
| Female Population | 50.8% | 55.5% | 50.5% |
| Male Population | 49.2% | 44.5% | 49.5% |
| Median Age | 45.3 | 46.2 | 38.4 |
| space3 | | | |
| Population - 2010 | 6,229 | 10,664 | 309,327,143 |
| Population - 2000 | 5,303 | 9,178 | 285,036,114 |
| Population - 1990 | 4,026 | 7,478 | 251,960,433 |
| Pop. 2000 to Now | 15.1% | 13.4% | 15.6% |
| Pop. 1990 to Now | 51.6% | 39.2% | 30.8% |
| space4 | | | |
| Population Density | 596.1 | 1,405.2 | 93.4 |
| Land Area | 11.1 | 7.8 | 3,531,905.4 |
| Water Area | 0.0 | 1.6 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Ontario, OH | Fox Lake, IL | United States |
| Age 0 to 4 | 6.0% | 6.5% | 5.9% |
| Age 5 to 9 | 5.9% | 2.6% | 6.1% |
| Age 10 to 14 | 5.0% | 6.7% | 6.6% |
| Age 15 to 17 | 1.8% | 1.9% | 3.9% |
| Age 18 to 20 | 2.2% | 3.0% | 4.0% |
| Age 21 to 24 | 6.1% | 3.3% | 5.2% |
| Age 25 to 34 | 12.7% | 11.2% | 13.8% |
| Age 35 to 44 | 10.1% | 13.7% | 12.9% |
| Age 45 to 54 | 12.5% | 14.3% | 12.6% |
| Age 55 to 59 | 8.9% | 10.5% | 6.7% |
| Age 60 to 64 | 8.2% | 6.2% | 6.3% |
| Age 65 to 74 | 10.3% | 12.8% | 9.6% |
| Age 75 to 84 | 6.3% | 5.4% | 4.5% |
| Age 85 and over | 4.0% | 1.7% | 1.9% |
| space1 | | | |
| Race | | | |
| | Ontario, OH | Fox Lake, IL | United States |
| White | 94.0% | 82.3% | 59.4% |
| Black | 0.9% | 2.2% | 12.2% |
| Asian | 3.1% | 1.0% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.2% | 0.2% |
| Other | 0.0% | 0.6% | 0.4% |
| Two or More Races | 0.8% | 2.6% | 3.2% |
| Hispanic | 1.2% | 11.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Ontario, OH | Fox Lake, IL | United States |
| Married Population | 63.0% | 47.3% | 49.8% |
| Currently Married | 61.4% | 46.9% | 48.0% |
| Married but Separated | 1.6% | 0.4% | 1.8% |
| Single Population | 37.0% | 52.7% | 50.2% |
| Never Married | 19.1% | 26.0% | 33.8% |
| Divorced | 11.1% | 19.8% | 10.8% |
| Widowed | 6.7% | 7.0% | 5.6% |
| space5 | | | |
| Household Size | 2.41 | 2.21 | 2.60 |
| Households | 2,726 | 4,929 | 124,010,992 |
| Family Households | 1,817 | 2,710 | 80,755,759 |
| Married couple, w/children | 27.4% | 23.6% | 30.5% |
| Married couple, no children | 58.8% | 52.3% | 42.9% |
| Non Family Households | 909 | 2,219 | 43,255,233 |
| Single householder, w/children | 8.6% | 17.0% | 15.8% |
| Single householder, no children | 5.2% | 7.1% | 10.8% |