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.
| Name | County | Diversity Index | |
|---|---|---|---|
| 1. | City of Hartford | Hartford | 89.3 |
| 2. | City of Bridgeport | Fairfield | 86.9 |
| 3. | East Hartford Census Designated Place | Hartford | 84.6 |
| 4. | City of New Haven | New Haven | 84.4 |
| 5. | City of New Britain | Hartford | 83.2 |
| 6. | City of Waterbury | New Haven | 83.1 |
| 7. | Willimantic Census Designated Place | Windham | 82.9 |
| 8. | City of New London | New London | 81.5 |
| 9. | City of Stamford | Fairfield | 79.0 |
| 10. | Poquonock Bridge Census Designated Place | New London | 78.4 |
| 11. | City of Danbury | Fairfield | 77.3 |
| 12. | City of Norwalk | Fairfield | 75.4 |
| 13. | City of Meriden | New Haven | 74.8 |
| 14. | City of West Haven | New Haven | 74.7 |
| 15. | City of Groton | New London | 74.6 |
| 16. | Byram Census Designated Place | Fairfield | 71.1 |
| 17. | Manchester Census Designated Place | Hartford | 70.5 |
| 18. | City of Norwich | New London | 68.3 |
| 19. | City of Ansonia | New Haven | 66.5 |
| 20. | Stratford Census Designated Place (historical) | Fairfield | 61.7 |
