Gahanna
- County:
- Franklin County
- County Seat:
- No
- Area (mi²):
- 12.432
- State:
- Ohio
Gahanna is a city located in Franklin County, Ohio. Gahanna has a 2026 population of 35,544. Gahanna is currently growing at a rate of 0.24% annually but its population has decreased by -0.45% since the most recent census, which recorded a population of 35,705 in 2020.