| | Okoboji, IA | Spirit Lake, IA | United States |
| Population | 840 | 5,301 | 329,725,481 |
| Female Population | 51.0% | 52.0% | 50.5% |
| Male Population | 49.1% | 48.0% | 49.5% |
| Median Age | 55 | 41.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 819 | 4,860 | 309,327,143 |
| Population - 2000 | 820 | 4,261 | 285,036,114 |
| Population - 1990 | 775 | 3,871 | 251,960,433 |
| Pop. 2000 to Now | -2.1% | 23.2% | 15.6% |
| Pop. 1990 to Now | 3.6% | 35.7% | 30.8% |
| space4 | | | |
| Population Density | 480.0 | 1,179.6 | 93.4 |
| Land Area | 1.8 | 4.5 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Okoboji, IA | Spirit Lake, IA | United States |
| Age 0 to 4 | 5.1% | 4.8% | 5.9% |
| Age 5 to 9 | 9.2% | 8.4% | 6.1% |
| Age 10 to 14 | 0.8% | 6.5% | 6.6% |
| Age 15 to 17 | 0.4% | 2.1% | 3.9% |
| Age 18 to 20 | 5.8% | 2.2% | 4.0% |
| Age 21 to 24 | 2.4% | 7.7% | 5.2% |
| Age 25 to 34 | 7.4% | 12.6% | 13.8% |
| Age 35 to 44 | 12.3% | 8.6% | 12.9% |
| Age 45 to 54 | 6.7% | 11.3% | 12.6% |
| Age 55 to 59 | 6.5% | 5.8% | 6.7% |
| Age 60 to 64 | 6.9% | 6.0% | 6.3% |
| Age 65 to 74 | 21.4% | 13.7% | 9.6% |
| Age 75 to 84 | 9.0% | 4.4% | 4.5% |
| Age 85 and over | 6.1% | 6.1% | 1.9% |
| space1 | | | |
| Race | | | |
| | Okoboji, IA | Spirit Lake, IA | United States |
| White | 93.1% | 92.1% | 59.4% |
| Black | 0.1% | 0.2% | 12.2% |
| Asian | 2.5% | 0.3% | 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 | 0.4% | 5.2% | 3.2% |
| Hispanic | 3.9% | 2.2% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Okoboji, IA | Spirit Lake, IA | United States |
| Married Population | 54.4% | 48.7% | 49.8% |
| Currently Married | 54.1% | 46.9% | 48.0% |
| Married but Separated | 0.3% | 1.8% | 1.8% |
| Single Population | 45.6% | 51.3% | 50.2% |
| Never Married | 20.8% | 30.0% | 33.8% |
| Divorced | 15.6% | 12.1% | 10.8% |
| Widowed | 9.3% | 9.2% | 5.6% |
| space5 | | | |
| Household Size | 1.94 | 2.05 | 2.60 |
| Households | 426 | 2,531 | 124,010,992 |
| Family Households | 198 | 1,227 | 80,755,759 |
| Married couple, w/children | 21.2% | 31.3% | 30.5% |
| Married couple, no children | 72.2% | 48.3% | 42.9% |
| Non Family Households | 228 | 1,304 | 43,255,233 |
| Single householder, w/children | 0.0% | 12.6% | 15.8% |
| Single householder, no children | 6.6% | 7.8% | 10.8% |