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. | Town of Bethany Beach | Sussex | 5.7 |
| 2. | Town of Fenwick Island | Sussex | 8.5 |
| 3. | Town of South Bethany | Sussex | 8.7 |
| 4. | City of Rehoboth Beach | Sussex | 13.6 |
| 5. | Town of Henlopen Acres | Sussex | 14.7 |
| 6. | Village of Ardentown | New Castle | 15.0 |
| 7. | Village of Arden | New Castle | 17.7 |
| 8. | Town of Ocean View | Sussex | 19.9 |
| 9. | Long Neck Census Designated Place | Sussex | 20.3 |
| 10. | Town of Dewey Beach | Sussex | 22.8 |
| 11. | City of Lewes | Sussex | 23.2 |
| 12. | Town of Millville | Sussex | 24.3 |
| 13. | Town of Slaughter Beach | Sussex | 24.3 |
| 14. | Town of Bellefonte | New Castle | 28.7 |
| 15. | Village of Ardencroft | New Castle | 29.5 |
| 16. | North Star Census Designated Place | New Castle | 34.1 |
| 17. | Town of Delmar | Sussex | 37.1 |
| 18. | Town of Kenton | Kent | 38.1 |
| 19. | Town of Bowers | Kent | 38.3 |
| 20. | Hockessin Census Designated Place | New Castle | 39.2 |
