| | Marin City, CA | Antioch, CA | United States |
| Population | 3,094 | 114,750 | 329,725,481 |
| Female Population | 53.2% | 51.7% | 50.5% |
| Male Population | 46.8% | 48.4% | 49.5% |
| Median Age | 40.5 | 37 | 38.4 |
| space3 | | | |
| Population - 2010 | 2,825 | 103,062 | 309,327,143 |
| Population - 2000 | 2,783 | 90,532 | 285,036,114 |
| Population - 1990 | 1,868 | 62,195 | 251,960,433 |
| Pop. 2000 to Now | 6.9% | 23.3% | 15.6% |
| Pop. 1990 to Now | 59.2% | 79.4% | 30.8% |
| space4 | | | |
| Population Density | 5,761.6 | 3,910.2 | 93.4 |
| Land Area | 0.5 | 29.3 | 3,531,905.4 |
| Water Area | 0.0 | 0.8 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Marin City, CA | Antioch, CA | United States |
| Age 0 to 4 | 5.9% | 5.7% | 5.9% |
| Age 5 to 9 | 7.0% | 6.0% | 6.1% |
| Age 10 to 14 | 6.4% | 7.2% | 6.6% |
| Age 15 to 17 | 2.9% | 5.1% | 3.9% |
| Age 18 to 20 | 2.0% | 3.7% | 4.0% |
| Age 21 to 24 | 1.4% | 5.6% | 5.2% |
| Age 25 to 34 | 17.4% | 13.8% | 13.8% |
| Age 35 to 44 | 13.7% | 13.1% | 12.9% |
| Age 45 to 54 | 20.4% | 12.7% | 12.6% |
| Age 55 to 59 | 7.0% | 7.4% | 6.7% |
| Age 60 to 64 | 3.1% | 6.9% | 6.3% |
| Age 65 to 74 | 5.4% | 8.4% | 9.6% |
| Age 75 to 84 | 4.0% | 3.2% | 4.5% |
| Age 85 and over | 3.5% | 1.2% | 1.9% |
| space1 | | | |
| Race | | | |
| | Marin City, CA | Antioch, CA | United States |
| White | 37.6% | 25.5% | 59.4% |
| Black | 25.0% | 19.5% | 12.2% |
| Asian | 12.5% | 12.2% | 5.6% |
| Native American | 0.0% | 0.2% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 1.2% | 0.2% |
| Other | 0.0% | 0.3% | 0.4% |
| Two or More Races | 12.5% | 6.1% | 3.2% |
| Hispanic | 12.4% | 35.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Marin City, CA | Antioch, CA | United States |
| Married Population | 41.6% | 44.7% | 49.8% |
| Currently Married | 37.9% | 42.9% | 48.0% |
| Married but Separated | 3.7% | 1.8% | 1.8% |
| Single Population | 58.4% | 55.3% | 50.2% |
| Never Married | 39.2% | 39.8% | 33.8% |
| Divorced | 12.9% | 10.6% | 10.8% |
| Widowed | 6.3% | 4.9% | 5.6% |
| space5 | | | |
| Household Size | 2.25 | 3.19 | 2.60 |
| Households | 1,374 | 35,742 | 124,010,992 |
| Family Households | 765 | 26,376 | 80,755,759 |
| Married couple, w/children | 29.2% | 29.5% | 30.5% |
| Married couple, no children | 20.5% | 35.3% | 42.9% |
| Non Family Households | 609 | 9,366 | 43,255,233 |
| Single householder, w/children | 34.0% | 21.1% | 15.8% |
| Single householder, no children | 16.3% | 14.1% | 10.8% |