| | Great Neck Estates, NY | Marblehead, MA | United States |
| Population | 2,935 | 20,397 | 329,725,481 |
| Female Population | 51.3% | 53.2% | 50.5% |
| Male Population | 48.7% | 46.8% | 49.5% |
| Median Age | 43.6 | 48.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 2,768 | 19,853 | 309,327,143 |
| Population - 2000 | 2,756 | 20,377 | 285,036,114 |
| Population - 1990 | 2,790 | 19,971 | 251,960,433 |
| Pop. 2000 to Now | 4.0% | 0.9% | 15.6% |
| Pop. 1990 to Now | 2.8% | 2.9% | 30.8% |
| space4 | | | |
| Population Density | 3,831.6 | 4,650.5 | 93.4 |
| Land Area | 0.8 | 4.4 | 3,531,905.4 |
| Water Area | 0.0 | 15.2 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Great Neck Estates, NY | Marblehead, MA | United States |
| Age 0 to 4 | 4.0% | 3.4% | 5.9% |
| Age 5 to 9 | 9.1% | 6.8% | 6.1% |
| Age 10 to 14 | 5.5% | 7.3% | 6.6% |
| Age 15 to 17 | 5.6% | 5.4% | 3.9% |
| Age 18 to 20 | 4.5% | 3.5% | 4.0% |
| Age 21 to 24 | 5.2% | 2.3% | 5.2% |
| Age 25 to 34 | 6.7% | 5.1% | 13.8% |
| Age 35 to 44 | 11.0% | 11.4% | 12.9% |
| Age 45 to 54 | 14.2% | 16.3% | 12.6% |
| Age 55 to 59 | 6.4% | 9.7% | 6.7% |
| Age 60 to 64 | 5.5% | 7.9% | 6.3% |
| Age 65 to 74 | 11.7% | 12.6% | 9.6% |
| Age 75 to 84 | 4.9% | 5.3% | 4.5% |
| Age 85 and over | 5.7% | 3.0% | 1.9% |
| space1 | | | |
| Race | | | |
| | Great Neck Estates, NY | Marblehead, MA | United States |
| White | 79.2% | 92.1% | 59.4% |
| Black | 0.0% | 0.4% | 12.2% |
| Asian | 13.6% | 1.6% | 5.6% |
| Native American | 4.1% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.1% | 0.4% | 0.4% |
| Two or More Races | 1.6% | 1.3% | 3.2% |
| Hispanic | 1.4% | 4.2% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Great Neck Estates, NY | Marblehead, MA | United States |
| Married Population | 67.5% | 62.4% | 49.8% |
| Currently Married | 67.5% | 61.9% | 48.0% |
| Married but Separated | 0.0% | 0.5% | 1.8% |
| Single Population | 32.5% | 37.6% | 50.2% |
| Never Married | 25.4% | 23.8% | 33.8% |
| Divorced | 4.1% | 9.2% | 10.8% |
| Widowed | 3.0% | 4.6% | 5.6% |
| space5 | | | |
| Household Size | 3.12 | 2.51 | 2.60 |
| Households | 942 | 8,075 | 124,010,992 |
| Family Households | 792 | 5,998 | 80,755,759 |
| Married couple, w/children | 34.6% | 36.7% | 30.5% |
| Married couple, no children | 59.2% | 48.8% | 42.9% |
| Non Family Households | 150 | 2,077 | 43,255,233 |
| Single householder, w/children | 2.9% | 8.1% | 15.8% |
| Single householder, no children | 3.3% | 6.4% | 10.8% |