Most racially diverse, US counties · 1990
US counties ranked by the CensusEasy Diversity Score (0 to 100), the chance two random residents are of a different race or ethnicity (1990 ACS). Aleutians East, Alaska leads at 85. 3,122 counties qualify in total. California carries 8 of the top 25 entries. The median across all 3,122 is 17.
Flip the list · Least racially diverse, US counties →UPDATED 2026-09-11 · DATA: US CENSUS BUREAU DECENNIAL CENSUS
Frequently asked
Which county has the highest diversity score?
Aleutians East, Alaska ranks #1 with 85 (1990 Decennial Census).
What are the top 5 counties by diversity score?
Aleutians East, Alaska, Queens County, New York, Kings County, New York, Los Angeles County, California, Cibola County, New Mexico.
How many counties are in this ranking?
3,122 counties qualify after filtering for population minimums and data availability. The ranking covers 1990 Decennial Census data.
How is diversity score measured?
CensusEasy Diversity Score (0 to 100): the chance that two random residents are of a different race or ethnicity, rescaled so 100 is a perfectly even split across all five groups. A Simpson diversity index over the five ACS race and ethnicity shares. Source: US Census Bureau, 1990 Decennial Census.