| | North Hempstead, NY | Nyack, NY | United States |
| Population | 236,910 | 7,303 | 329,725,481 |
| Female Population | 50.6% | 52.4% | 50.5% |
| Male Population | 49.4% | 47.6% | 49.5% |
| Median Age | 42.2 | 40.4 | 38.4 |
| space3 | | | |
| Population - 2010 | 226,547 | 6,787 | 309,327,143 |
| Population - 2000 | 222,611 | 6,737 | 285,036,114 |
| Population - 1990 | 211,393 | 6,558 | 251,960,433 |
| Pop. 2000 to Now | 3.5% | 5.9% | 15.6% |
| Pop. 1990 to Now | 9.0% | 8.8% | 30.8% |
| space4 | | | |
| Population Density | 4,427.0 | 9,484.4 | 93.4 |
| Land Area | 53.5 | 0.8 | 3,531,905.4 |
| Water Area | 15.6 | 0.8 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | North Hempstead, NY | Nyack, NY | United States |
| Age 0 to 4 | 5.4% | 4.8% | 5.9% |
| Age 5 to 9 | 6.8% | 5.3% | 6.1% |
| Age 10 to 14 | 6.9% | 6.1% | 6.6% |
| Age 15 to 17 | 4.1% | 1.5% | 3.9% |
| Age 18 to 20 | 3.2% | 0.8% | 4.0% |
| Age 21 to 24 | 4.5% | 4.7% | 5.2% |
| Age 25 to 34 | 10.5% | 13.5% | 13.8% |
| Age 35 to 44 | 12.6% | 18.2% | 12.9% |
| Age 45 to 54 | 13.7% | 11.1% | 12.6% |
| Age 55 to 59 | 6.8% | 7.2% | 6.7% |
| Age 60 to 64 | 7.1% | 6.0% | 6.3% |
| Age 65 to 74 | 9.9% | 13.4% | 9.6% |
| Age 75 to 84 | 5.3% | 6.0% | 4.5% |
| Age 85 and over | 3.2% | 1.5% | 1.9% |
| space1 | | | |
| Race | | | |
| | North Hempstead, NY | Nyack, NY | United States |
| White | 57.8% | 54.8% | 59.4% |
| Black | 5.0% | 19.1% | 12.2% |
| Asian | 19.7% | 5.1% | 5.6% |
| Native American | 0.1% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 1.2% | 0.8% | 0.4% |
| Two or More Races | 2.0% | 1.7% | 3.2% |
| Hispanic | 14.1% | 18.5% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | North Hempstead, NY | Nyack, NY | United States |
| Married Population | 59.0% | 41.8% | 49.8% |
| Currently Married | 57.9% | 37.9% | 48.0% |
| Married but Separated | 1.1% | 3.9% | 1.8% |
| Single Population | 41.0% | 58.2% | 50.2% |
| Never Married | 29.0% | 41.7% | 33.8% |
| Divorced | 6.1% | 12.9% | 10.8% |
| Widowed | 5.8% | 3.6% | 5.6% |
| space5 | | | |
| Household Size | 2.97 | 2.29 | 2.60 |
| Households | 78,822 | 3,190 | 124,010,992 |
| Family Households | 60,267 | 1,478 | 80,755,759 |
| Married couple, w/children | 38.4% | 25.4% | 30.5% |
| Married couple, no children | 45.2% | 47.4% | 42.9% |
| Non Family Households | 18,555 | 1,712 | 43,255,233 |
| Single householder, w/children | 7.4% | 16.8% | 15.8% |
| Single householder, no children | 9.0% | 10.4% | 10.8% |