| | Kingston, NH | Marshfield, MA | United States |
| Population | 6,177 | 25,793 | 329,725,481 |
| Female Population | 43.8% | 51.1% | 50.5% |
| Male Population | 56.2% | 49.0% | 49.5% |
| Median Age | 49 | 46.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 6,037 | 25,207 | 309,327,143 |
| Population - 2000 | 5,862 | 24,324 | 285,036,114 |
| Population - 1990 | 5,591 | 21,531 | 251,960,433 |
| Pop. 2000 to Now | 9.6% | 7.0% | 15.6% |
| Pop. 1990 to Now | 14.9% | 20.9% | 30.8% |
| space4 | | | |
| Population Density | 314.3 | 901.2 | 93.4 |
| Land Area | 19.7 | 28.6 | 3,531,905.4 |
| Water Area | 1.2 | 3.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Kingston, NH | Marshfield, MA | United States |
| Age 0 to 4 | 1.7% | 4.6% | 5.9% |
| Age 5 to 9 | 4.3% | 6.7% | 6.1% |
| Age 10 to 14 | 5.2% | 5.1% | 6.6% |
| Age 15 to 17 | 5.1% | 4.1% | 3.9% |
| Age 18 to 20 | 2.1% | 2.8% | 4.0% |
| Age 21 to 24 | 5.5% | 5.4% | 5.2% |
| Age 25 to 34 | 10.7% | 7.5% | 13.8% |
| Age 35 to 44 | 9.6% | 12.6% | 12.9% |
| Age 45 to 54 | 16.4% | 16.5% | 12.6% |
| Age 55 to 59 | 7.0% | 8.6% | 6.7% |
| Age 60 to 64 | 12.2% | 7.7% | 6.3% |
| Age 65 to 74 | 13.4% | 11.1% | 9.6% |
| Age 75 to 84 | 4.7% | 5.0% | 4.5% |
| Age 85 and over | 2.2% | 2.4% | 1.9% |
| space1 | | | |
| Race | | | |
| | Kingston, NH | Marshfield, MA | United States |
| White | 96.2% | 95.2% | 59.4% |
| Black | 0.0% | 0.5% | 12.2% |
| Asian | 0.5% | 0.7% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.1% | 0.2% |
| Other | 0.0% | 0.1% | 0.4% |
| Two or More Races | 1.9% | 0.8% | 3.2% |
| Hispanic | 1.3% | 2.6% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Kingston, NH | Marshfield, MA | United States |
| Married Population | 43.7% | 56.8% | 49.8% |
| Currently Married | 43.7% | 56.6% | 48.0% |
| Married but Separated | 0.0% | 0.2% | 1.8% |
| Single Population | 56.3% | 43.2% | 50.2% |
| Never Married | 31.2% | 27.5% | 33.8% |
| Divorced | 16.9% | 10.4% | 10.8% |
| Widowed | 8.2% | 5.3% | 5.6% |
| space5 | | | |
| Household Size | 2.30 | 2.54 | 2.60 |
| Households | 2,687 | 10,094 | 124,010,992 |
| Family Households | 1,586 | 7,274 | 80,755,759 |
| Married couple, w/children | 27.4% | 32.7% | 30.5% |
| Married couple, no children | 47.3% | 46.4% | 42.9% |
| Non Family Households | 1,101 | 2,820 | 43,255,233 |
| Single householder, w/children | 15.2% | 6.9% | 15.8% |
| Single householder, no children | 10.1% | 14.0% | 10.8% |