| Statistic | Mark Twain | St. Louis | Missouri |
| Population | 4,569 | 316,030 | 6,059,651 |
| Population density (sq mi) | 2,164 | 5,101 | 86 |
| Median age | 43.7 | 34.8 | 38.3 |
| Male/Female ratio | 1.0:1 | 0.9:1 | 1.0:1 |
| Married (15yrs & older) | n/a | 37% | 57% |
| Speak English | n/a | 91% | 94% |
| Speak Spanish | n/a | 3% | 3% |
| Race | Mark Twain | St. Louis | Missouri |
| Caucasian | 2.93% | 45.64% | 82.53% |
| African American | 96.20% | 47.90% | 11.58% |
| Asian | 0.24% | 3.06% | 1.78% |
| American Indian | 0.13% | 0.23% | 0.42% |
| Native Hawaiian | 0.00% | 0.05% | 0.11% |
| Mixed race | 0.50% | 2.23% | 2.44% |
| Other race | 0.00% | 0.89% | 1.13% |