| | California, PA | Oakmont, PA | United States |
| Population | 5,628 | 6,722 | 329,725,481 |
| Female Population | 52.5% | 51.4% | 50.5% |
| Male Population | 47.5% | 48.6% | 49.5% |
| Median Age | 22.8 | 45.8 | 38.4 |
| space3 | | | |
| Population - 2010 | 6,784 | 6,304 | 309,327,143 |
| Population - 2000 | 5,274 | 6,911 | 285,036,114 |
| Population - 1990 | 5,748 | 6,961 | 251,960,433 |
| Pop. 2000 to Now | 18.7% | -5.0% | 15.6% |
| Pop. 1990 to Now | 8.9% | -5.7% | 30.8% |
| space4 | | | |
| Population Density | 511.1 | 4,233.0 | 93.4 |
| Land Area | 11.0 | 1.6 | 3,531,905.4 |
| Water Area | 0.2 | 0.2 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | California, PA | Oakmont, PA | United States |
| Age 0 to 4 | 2.0% | 4.7% | 5.9% |
| Age 5 to 9 | 5.5% | 6.5% | 6.1% |
| Age 10 to 14 | 3.2% | 5.0% | 6.6% |
| Age 15 to 17 | 4.3% | 2.1% | 3.9% |
| Age 18 to 20 | 25.1% | 1.7% | 4.0% |
| Age 21 to 24 | 14.6% | 2.0% | 5.2% |
| Age 25 to 34 | 7.5% | 11.7% | 13.8% |
| Age 35 to 44 | 7.5% | 15.8% | 12.9% |
| Age 45 to 54 | 7.0% | 13.9% | 12.6% |
| Age 55 to 59 | 4.2% | 6.3% | 6.7% |
| Age 60 to 64 | 4.5% | 7.2% | 6.3% |
| Age 65 to 74 | 6.3% | 11.3% | 9.6% |
| Age 75 to 84 | 3.3% | 6.8% | 4.5% |
| Age 85 and over | 4.9% | 4.9% | 1.9% |
| space1 | | | |
| Race | | | |
| | California, PA | Oakmont, PA | United States |
| White | 78.9% | 95.1% | 59.4% |
| Black | 12.1% | 0.5% | 12.2% |
| Asian | 0.5% | 0.1% | 5.6% |
| Native American | 0.0% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.1% | 0.0% | 0.4% |
| Two or More Races | 5.6% | 2.7% | 3.2% |
| Hispanic | 2.9% | 1.5% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | California, PA | Oakmont, PA | United States |
| Married Population | 28.3% | 56.5% | 49.8% |
| Currently Married | 25.8% | 55.1% | 48.0% |
| Married but Separated | 2.5% | 1.4% | 1.8% |
| Single Population | 71.7% | 43.5% | 50.2% |
| Never Married | 63.0% | 24.0% | 33.8% |
| Divorced | 5.0% | 12.1% | 10.8% |
| Widowed | 3.7% | 7.4% | 5.6% |
| space5 | | | |
| Household Size | 2.24 | 2.01 | 2.60 |
| Households | 1,805 | 3,274 | 124,010,992 |
| Family Households | 900 | 1,644 | 80,755,759 |
| Married couple, w/children | 32.4% | 40.0% | 30.5% |
| Married couple, no children | 35.2% | 49.1% | 42.9% |
| Non Family Households | 905 | 1,630 | 43,255,233 |
| Single householder, w/children | 11.8% | 5.4% | 15.8% |
| Single householder, no children | 20.6% | 5.4% | 10.8% |