| | Inman, KS | St. John, KS | United States |
| Population | 1,485 | 1,245 | 329,725,481 |
| Female Population | 54.3% | 47.4% | 50.5% |
| Male Population | 45.7% | 52.6% | 49.5% |
| Median Age | 46.8 | 38 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,383 | 1,292 | 309,327,143 |
| Population - 2000 | 1,142 | 1,318 | 285,036,114 |
| Population - 1990 | 1,035 | 1,357 | 251,960,433 |
| Pop. 2000 to Now | 15.9% | -13.6% | 15.6% |
| Pop. 1990 to Now | 27.9% | -16.1% | 30.8% |
| space4 | | | |
| Population Density | 1,928.6 | 640.4 | 93.4 |
| Land Area | 0.8 | 1.9 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Inman, KS | St. John, KS | United States |
| Age 0 to 4 | 5.6% | 7.6% | 5.9% |
| Age 5 to 9 | 5.6% | 7.1% | 6.1% |
| Age 10 to 14 | 5.4% | 6.4% | 6.6% |
| Age 15 to 17 | 6.9% | 4.2% | 3.9% |
| Age 18 to 20 | 3.0% | 5.4% | 4.0% |
| Age 21 to 24 | 2.9% | 6.3% | 5.2% |
| Age 25 to 34 | 8.1% | 12.6% | 13.8% |
| Age 35 to 44 | 9.4% | 7.8% | 12.9% |
| Age 45 to 54 | 11.2% | 11.9% | 12.6% |
| Age 55 to 59 | 2.1% | 4.5% | 6.7% |
| Age 60 to 64 | 5.6% | 4.7% | 6.3% |
| Age 65 to 74 | 13.4% | 10.2% | 9.6% |
| Age 75 to 84 | 10.5% | 7.3% | 4.5% |
| Age 85 and over | 10.3% | 4.0% | 1.9% |
| space1 | | | |
| Race | | | |
| | Inman, KS | St. John, KS | United States |
| White | 93.5% | 74.7% | 59.4% |
| Black | 0.1% | 0.0% | 12.2% |
| Asian | 0.0% | 0.0% | 5.6% |
| Native American | 1.1% | 2.9% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 0.7% | 1.8% | 3.2% |
| Hispanic | 4.6% | 20.6% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Inman, KS | St. John, KS | United States |
| Married Population | 65.5% | 51.1% | 49.8% |
| Currently Married | 65.5% | 50.7% | 48.0% |
| Married but Separated | 0.0% | 0.4% | 1.8% |
| Single Population | 34.5% | 48.9% | 50.2% |
| Never Married | 21.7% | 24.5% | 33.8% |
| Divorced | 4.1% | 12.8% | 10.8% |
| Widowed | 8.7% | 11.5% | 5.6% |
| space5 | | | |
| Household Size | 2.71 | 2.94 | 2.60 |
| Households | 513 | 407 | 124,010,992 |
| Family Households | 381 | 257 | 80,755,759 |
| Married couple, w/children | 31.8% | 41.2% | 30.5% |
| Married couple, no children | 54.1% | 44.0% | 42.9% |
| Non Family Households | 132 | 150 | 43,255,233 |
| Single householder, w/children | 12.1% | 9.3% | 15.8% |
| Single householder, no children | 2.1% | 5.4% | 10.8% |