| | Okemah, OK | Nixa, MO | United States |
| Population | 3,113 | 22,925 | 329,725,481 |
| Female Population | 49.9% | 49.9% | 50.5% |
| Male Population | 50.2% | 50.1% | 49.5% |
| Median Age | 35 | 34.8 | 38.4 |
| space3 | | | |
| Population - 2010 | 3,225 | 19,157 | 309,327,143 |
| Population - 2000 | 3,038 | 12,124 | 285,036,114 |
| Population - 1990 | 3,085 | 4,707 | 251,960,433 |
| Pop. 2000 to Now | 0.3% | 92.4% | 15.6% |
| Pop. 1990 to Now | -1.2% | 395.6% | 30.8% |
| space4 | | | |
| Population Density | 1,231.4 | 2,604.5 | 93.4 |
| Land Area | 2.5 | 8.8 | 3,531,905.4 |
| Water Area | 0.1 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Okemah, OK | Nixa, MO | United States |
| Age 0 to 4 | 6.8% | 7.8% | 5.9% |
| Age 5 to 9 | 10.1% | 8.3% | 6.1% |
| Age 10 to 14 | 6.7% | 6.6% | 6.6% |
| Age 15 to 17 | 4.2% | 4.6% | 3.9% |
| Age 18 to 20 | 2.9% | 2.5% | 4.0% |
| Age 21 to 24 | 4.7% | 3.7% | 5.2% |
| Age 25 to 34 | 14.5% | 16.7% | 13.8% |
| Age 35 to 44 | 12.4% | 12.2% | 12.9% |
| Age 45 to 54 | 11.3% | 12.1% | 12.6% |
| Age 55 to 59 | 6.0% | 7.4% | 6.7% |
| Age 60 to 64 | 4.7% | 4.5% | 6.3% |
| Age 65 to 74 | 7.6% | 8.2% | 9.6% |
| Age 75 to 84 | 6.0% | 4.0% | 4.5% |
| Age 85 and over | 2.0% | 1.4% | 1.9% |
| space1 | | | |
| Race | | | |
| | Okemah, OK | Nixa, MO | United States |
| White | 60.0% | 89.2% | 59.4% |
| Black | 1.4% | 1.1% | 12.2% |
| Asian | 0.0% | 1.5% | 5.6% |
| Native American | 18.4% | 0.3% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.4% | 0.4% |
| Two or More Races | 14.0% | 2.9% | 3.2% |
| Hispanic | 6.1% | 4.7% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Okemah, OK | Nixa, MO | United States |
| Married Population | 43.1% | 60.6% | 49.8% |
| Currently Married | 38.4% | 59.2% | 48.0% |
| Married but Separated | 4.7% | 1.4% | 1.8% |
| Single Population | 56.9% | 39.4% | 50.2% |
| Never Married | 30.0% | 21.0% | 33.8% |
| Divorced | 17.1% | 14.2% | 10.8% |
| Widowed | 9.8% | 4.3% | 5.6% |
| space5 | | | |
| Household Size | 2.74 | 2.73 | 2.60 |
| Households | 1,078 | 8,355 | 124,010,992 |
| Family Households | 744 | 6,255 | 80,755,759 |
| Married couple, w/children | 17.6% | 40.6% | 30.5% |
| Married couple, no children | 34.3% | 39.7% | 42.9% |
| Non Family Households | 334 | 2,100 | 43,255,233 |
| Single householder, w/children | 32.8% | 13.2% | 15.8% |
| Single householder, no children | 15.3% | 6.5% | 10.8% |