| | Manti, UT | Grantsville, UT | United States |
| Population | 3,460 | 12,331 | 329,725,481 |
| Female Population | 48.0% | 46.7% | 50.5% |
| Male Population | 52.0% | 53.3% | 49.5% |
| Median Age | 35 | 27.9 | 38.4 |
| space3 | | | |
| Population - 2010 | 3,444 | 8,972 | 309,327,143 |
| Population - 2000 | 3,040 | 6,015 | 285,036,114 |
| Population - 1990 | 2,268 | 4,500 | 251,960,433 |
| Pop. 2000 to Now | 24.7% | 106.3% | 15.6% |
| Pop. 1990 to Now | 67.1% | 175.8% | 30.8% |
| space4 | | | |
| Population Density | 1,393.5 | 329.4 | 93.4 |
| Land Area | 2.5 | 37.4 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Manti, UT | Grantsville, UT | United States |
| Age 0 to 4 | 6.6% | 7.1% | 5.9% |
| Age 5 to 9 | 8.1% | 11.3% | 6.1% |
| Age 10 to 14 | 8.2% | 13.6% | 6.6% |
| Age 15 to 17 | 4.6% | 6.2% | 3.9% |
| Age 18 to 20 | 5.2% | 2.8% | 4.0% |
| Age 21 to 24 | 4.6% | 4.6% | 5.2% |
| Age 25 to 34 | 12.7% | 11.4% | 13.8% |
| Age 35 to 44 | 12.7% | 14.8% | 12.9% |
| Age 45 to 54 | 12.1% | 11.9% | 12.6% |
| Age 55 to 59 | 2.8% | 3.9% | 6.7% |
| Age 60 to 64 | 6.6% | 4.3% | 6.3% |
| Age 65 to 74 | 10.1% | 5.4% | 9.6% |
| Age 75 to 84 | 4.2% | 2.0% | 4.5% |
| Age 85 and over | 1.5% | 0.7% | 1.9% |
| space1 | | | |
| Race | | | |
| | Manti, UT | Grantsville, UT | United States |
| White | 88.4% | 90.8% | 59.4% |
| Black | 2.3% | 0.2% | 12.2% |
| Asian | 0.3% | 1.1% | 5.6% |
| Native American | 0.8% | 0.5% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.1% | 0.0% | 0.4% |
| Two or More Races | 2.1% | 0.4% | 3.2% |
| Hispanic | 5.9% | 7.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Manti, UT | Grantsville, UT | United States |
| Married Population | 60.8% | 60.3% | 49.8% |
| Currently Married | 59.2% | 59.5% | 48.0% |
| Married but Separated | 1.5% | 0.8% | 1.8% |
| Single Population | 39.2% | 39.7% | 50.2% |
| Never Married | 27.1% | 28.8% | 33.8% |
| Divorced | 8.7% | 7.4% | 10.8% |
| Widowed | 3.4% | 3.5% | 5.6% |
| space5 | | | |
| Household Size | 2.99 | 3.62 | 2.60 |
| Households | 1,086 | 3,402 | 124,010,992 |
| Family Households | 832 | 3,018 | 80,755,759 |
| Married couple, w/children | 48.1% | 50.3% | 30.5% |
| Married couple, no children | 42.8% | 27.2% | 42.9% |
| Non Family Households | 254 | 384 | 43,255,233 |
| Single householder, w/children | 6.3% | 16.4% | 15.8% |
| Single householder, no children | 2.9% | 6.1% | 10.8% |