| | Tarentum, PA | Lansdale, PA | United States |
| Population | 4,359 | 18,509 | 329,725,481 |
| Female Population | 52.3% | 48.6% | 50.5% |
| Male Population | 47.7% | 51.4% | 49.5% |
| Median Age | 46.2 | 38.6 | 38.4 |
| space3 | | | |
| Population - 2010 | 4,537 | 16,291 | 309,327,143 |
| Population - 2000 | 4,993 | 16,071 | 285,036,114 |
| Population - 1990 | 5,674 | 16,362 | 251,960,433 |
| Pop. 2000 to Now | -13.1% | 7.9% | 15.6% |
| Pop. 1990 to Now | -23.6% | 6.0% | 30.8% |
| space4 | | | |
| Population Density | 3,558.4 | 6,184.1 | 93.4 |
| Land Area | 1.2 | 3.0 | 3,531,905.4 |
| Water Area | 0.2 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Tarentum, PA | Lansdale, PA | United States |
| Age 0 to 4 | 6.5% | 5.2% | 5.9% |
| Age 5 to 9 | 5.8% | 5.7% | 6.1% |
| Age 10 to 14 | 5.2% | 6.0% | 6.6% |
| Age 15 to 17 | 3.7% | 4.7% | 3.9% |
| Age 18 to 20 | 0.8% | 3.7% | 4.0% |
| Age 21 to 24 | 6.2% | 4.5% | 5.2% |
| Age 25 to 34 | 10.1% | 14.5% | 13.8% |
| Age 35 to 44 | 10.6% | 15.8% | 12.9% |
| Age 45 to 54 | 12.0% | 13.4% | 12.6% |
| Age 55 to 59 | 7.1% | 5.9% | 6.7% |
| Age 60 to 64 | 11.3% | 6.3% | 6.3% |
| Age 65 to 74 | 14.8% | 8.0% | 9.6% |
| Age 75 to 84 | 1.3% | 4.3% | 4.5% |
| Age 85 and over | 4.7% | 2.0% | 1.9% |
| space1 | | | |
| Race | | | |
| | Tarentum, PA | Lansdale, PA | United States |
| White | 85.1% | 70.8% | 59.4% |
| Black | 6.4% | 6.5% | 12.2% |
| Asian | 0.0% | 14.2% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 5.1% | 2.2% | 3.2% |
| Hispanic | 3.5% | 6.3% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Tarentum, PA | Lansdale, PA | United States |
| Married Population | 39.1% | 50.1% | 49.8% |
| Currently Married | 34.9% | 49.2% | 48.0% |
| Married but Separated | 4.3% | 0.8% | 1.8% |
| Single Population | 60.9% | 49.9% | 50.2% |
| Never Married | 32.6% | 35.8% | 33.8% |
| Divorced | 17.7% | 8.8% | 10.8% |
| Widowed | 10.6% | 5.3% | 5.6% |
| space5 | | | |
| Household Size | 2.10 | 2.59 | 2.60 |
| Households | 2,067 | 7,006 | 124,010,992 |
| Family Households | 979 | 4,525 | 80,755,759 |
| Married couple, w/children | 23.7% | 34.1% | 30.5% |
| Married couple, no children | 39.8% | 38.9% | 42.9% |
| Non Family Households | 1,088 | 2,481 | 43,255,233 |
| Single householder, w/children | 16.4% | 14.0% | 15.8% |
| Single householder, no children | 20.0% | 13.0% | 10.8% |