Karns City
- County:
- Butler County
- County Seat:
- No
- Area (mi²):
- 0.363
- State:
- Pennsylvania
Karns City is a borough located in Butler County, Pennsylvania. Karns City has a 2026 population of 166. Karns City is currently declining at a rate of -0.6% annually and its population has decreased by -3.49% since the most recent census, which recorded a population of 172 in 2020.
The median household income in Karns City is $49,583 with a poverty rate of 21.65%. The median age in Karns City is 39 years: 47.3 years for males, and 33 years for females. For every 100 females there are 61.7 males.