| | San Martin, CA | Newark, CA | United States |
| Population | 6,655 | 47,815 | 329,725,481 |
| Female Population | 52.5% | 49.5% | 50.5% |
| Male Population | 47.5% | 50.5% | 49.5% |
| Median Age | 50.8 | 36.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 7,250 | 42,619 | 309,327,143 |
| Population - 2000 | 4,230 | 42,471 | 285,036,114 |
| Population - 1990 | 1,713 | 37,861 | 251,960,433 |
| Pop. 2000 to Now | 72.1% | 17.0% | 15.6% |
| Pop. 1990 to Now | 325.0% | 31.3% | 30.8% |
| space4 | | | |
| Population Density | 574.0 | 3,446.1 | 93.4 |
| Land Area | 11.6 | 13.9 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | San Martin, CA | Newark, CA | United States |
| Age 0 to 4 | 3.5% | 6.6% | 5.9% |
| Age 5 to 9 | 3.2% | 5.4% | 6.1% |
| Age 10 to 14 | 4.6% | 4.8% | 6.6% |
| Age 15 to 17 | 2.6% | 3.6% | 3.9% |
| Age 18 to 20 | 2.6% | 3.0% | 4.0% |
| Age 21 to 24 | 4.0% | 4.5% | 5.2% |
| Age 25 to 34 | 14.1% | 18.9% | 13.8% |
| Age 35 to 44 | 9.8% | 14.4% | 12.9% |
| Age 45 to 54 | 16.1% | 13.0% | 12.6% |
| Age 55 to 59 | 9.9% | 7.7% | 6.7% |
| Age 60 to 64 | 7.5% | 5.9% | 6.3% |
| Age 65 to 74 | 13.6% | 6.7% | 9.6% |
| Age 75 to 84 | 5.6% | 4.2% | 4.5% |
| Age 85 and over | 3.0% | 1.5% | 1.9% |
| space1 | | | |
| Race | | | |
| | San Martin, CA | Newark, CA | United States |
| White | 44.4% | 22.2% | 59.4% |
| Black | 0.5% | 3.4% | 12.2% |
| Asian | 3.5% | 38.6% | 5.6% |
| Native American | 0.3% | 0.4% | 0.6% |
| Hawaiian, Pacific Islander | 0.3% | 1.7% | 0.2% |
| Other | 0.0% | 0.4% | 0.4% |
| Two or More Races | 3.0% | 4.1% | 3.2% |
| Hispanic | 47.9% | 29.2% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | San Martin, CA | Newark, CA | United States |
| Married Population | 51.2% | 54.5% | 49.8% |
| Currently Married | 50.0% | 53.7% | 48.0% |
| Married but Separated | 1.3% | 0.8% | 1.8% |
| Single Population | 48.8% | 45.5% | 50.2% |
| Never Married | 34.6% | 34.2% | 33.8% |
| Divorced | 9.8% | 7.3% | 10.8% |
| Widowed | 4.4% | 3.9% | 5.6% |
| space5 | | | |
| Household Size | 3.16 | 3.32 | 2.60 |
| Households | 2,040 | 14,354 | 124,010,992 |
| Family Households | 1,574 | 11,705 | 80,755,759 |
| Married couple, w/children | 29.7% | 36.1% | 30.5% |
| Married couple, no children | 50.5% | 39.8% | 42.9% |
| Non Family Households | 466 | 2,649 | 43,255,233 |
| Single householder, w/children | 6.7% | 10.1% | 15.8% |
| Single householder, no children | 13.1% | 14.0% | 10.8% |