| | Manhasset, NY | Jacksonville Beach, FL | United States |
| Population | 8,093 | 23,492 | 329,725,481 |
| Female Population | 52.7% | 47.4% | 50.5% |
| Male Population | 47.3% | 52.6% | 49.5% |
| Median Age | 43 | 41.9 | 38.4 |
| space3 | | | |
| Population - 2010 | 8,207 | 21,377 | 309,327,143 |
| Population - 2000 | 8,362 | 20,990 | 285,036,114 |
| Population - 1990 | 7,718 | 17,839 | 251,960,433 |
| Pop. 2000 to Now | -5.5% | 12.5% | 15.6% |
| Pop. 1990 to Now | 2.4% | 32.3% | 30.8% |
| space4 | | | |
| Population Density | 3,391.9 | 3,200.1 | 93.4 |
| Land Area | 2.4 | 7.3 | 3,531,905.4 |
| Water Area | 0.0 | 14.6 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Manhasset, NY | Jacksonville Beach, FL | United States |
| Age 0 to 4 | 4.2% | 4.4% | 5.9% |
| Age 5 to 9 | 6.3% | 4.2% | 6.1% |
| Age 10 to 14 | 9.4% | 5.2% | 6.6% |
| Age 15 to 17 | 5.7% | 4.5% | 3.9% |
| Age 18 to 20 | 2.7% | 1.5% | 4.0% |
| Age 21 to 24 | 5.9% | 3.8% | 5.2% |
| Age 25 to 34 | 6.3% | 16.6% | 13.8% |
| Age 35 to 44 | 12.4% | 12.9% | 12.9% |
| Age 45 to 54 | 19.0% | 14.0% | 12.6% |
| Age 55 to 59 | 6.2% | 6.9% | 6.7% |
| Age 60 to 64 | 5.5% | 7.5% | 6.3% |
| Age 65 to 74 | 9.4% | 12.1% | 9.6% |
| Age 75 to 84 | 4.3% | 4.3% | 4.5% |
| Age 85 and over | 2.7% | 2.1% | 1.9% |
| space1 | | | |
| Race | | | |
| | Manhasset, NY | Jacksonville Beach, FL | United States |
| White | 54.8% | 87.6% | 59.4% |
| Black | 14.6% | 1.4% | 12.2% |
| Asian | 17.9% | 1.9% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.5% | 0.4% | 0.4% |
| Two or More Races | 3.1% | 3.3% | 3.2% |
| Hispanic | 9.2% | 5.4% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Manhasset, NY | Jacksonville Beach, FL | United States |
| Married Population | 57.6% | 47.3% | 49.8% |
| Currently Married | 56.7% | 45.5% | 48.0% |
| Married but Separated | 0.9% | 1.8% | 1.8% |
| Single Population | 42.4% | 52.7% | 50.2% |
| Never Married | 29.1% | 33.1% | 33.8% |
| Divorced | 7.8% | 14.8% | 10.8% |
| Widowed | 5.5% | 4.8% | 5.6% |
| space5 | | | |
| Household Size | 3.03 | 2.19 | 2.60 |
| Households | 2,528 | 10,655 | 124,010,992 |
| Family Households | 2,031 | 5,929 | 80,755,759 |
| Married couple, w/children | 46.7% | 23.0% | 30.5% |
| Married couple, no children | 36.8% | 53.2% | 42.9% |
| Non Family Households | 497 | 4,726 | 43,255,233 |
| Single householder, w/children | 7.4% | 16.4% | 15.8% |
| Single householder, no children | 9.1% | 7.4% | 10.8% |