| Place Name | Karns City |
| Place Type | Borough |
| ZIP Code(s) | 16041 |
| County | Butler County |
| Area Code(s) | 724,878 |
| Timezone | Eastern Daylight Time (EDT) |
| Population (2022) | 258 |
| Population Growth Rate (2010-19) | -16.27% |
| Majority Ethnicity | White 99.47% |
| Metro/Micro Stats Area | Pittsburgh, PA |
| US Congressional District(s) | Pennsylvania 3rd |
| State House Districts | 11 |
| State Senate Districts | 41 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 99.47% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0.53% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0% |