The Diversity Index is a scale of 0 to 100 that represents the likelyhood that two persons, chosen at random from the same area, belong to different race or ethnic groups. If an area's entire population belongs to one race AND one ethnic group, then the area has zero diversity. An area's diversity index increases to 100 when the population is evenly divided into two or more race/ethnic groups.
| County | Diversity Index | |
|---|---|---|
| 1. | Cuyahoga County | 59.5 |
| 2. | Franklin County | 59.1 |
| 3. | Hamilton County | 53.3 |
| 4. | Lucas County | 53.1 |
| 5. | Montgomery County | 47.9 |
| 6. | Mahoning County | 44.7 |
| 7. | Lorain County | 44.3 |
| 8. | Summit County | 41.5 |
| 9. | Butler County | 39.4 |
| 10. | Allen County | 36.3 |
| 11. | Sandusky County | 35.2 |
| 12. | Erie County | 33.4 |
| 13. | Defiance County | 32.8 |
| 14. | Clark County | 32.7 |
| 15. | Greene County | 31.9 |
| 16. | Delaware County | 31.4 |
| 17. | Fairfield County | 29.3 |
| 18. | Warren County | 29.1 |
| 19. | Lake County | 28.3 |
| 20. | Richland County | 27.9 |
