The most and least diverse states in America, and how much every state changed since 1990

Pick two people at random in Hawaii and there is an 89.7 percent chance they belong to different racial or ethnic groups. Do the same in Vermont and the odds are 23.5 percent.

That number is the CensusEasy diversity score. It measures the chance that two people picked at random from the same place fall into different race or Hispanic-origin groups. A score of 0 would mean the entire population falls into one same group, while a score closer to 100 means the population is more evenly divided among several groups.

Hawaii is the only state with no racial majority anywhere close to one: 36.4 percent Asian, 20.9 percent white, 9.9 percent Hispanic, and a large share reporting two or more races. California is 40.2 percent Hispanic, 33.8 percent white, and 15.3 percent Asian. Texas is 39.7 percent Hispanic and 39.1 percent white, the closest thing in the country to a two-way split.

The least diverse states

Three states cluster at the bottom for diversity. Vermont and Maine both score 23.5, and West Virginia scores 24.0. Vermont and Maine are each 89.9 percent white. West Virginia is 89.7 percent white with a 3.1 percent Black population, the largest minority group in the state.

Then come New Hampshire at 29.9, Montana at 36.0, Iowa at 39.2, North Dakota at 40.1, and Wyoming at 40.3. Every state in that group is rural, northern or mountain, and has received little of the immigration that reshaped the rest of the country since 1990.

Where the change has been biggest

Every state got more diverse between 1990 and 2024, without exception.

Minnesota and Nebraska, both overwhelmingly white a generation ago, have crossed 50 in our diversity score. The states with the smallest gains are the ones that were already diverse, New Mexico at 73.9 to 77.6, and the ones that started lowest and stayed low, West Virginia at 9.9 to 24.0.

City-level results are in the most diverse cities in America, neighborhoods in the most diverse neighborhoods, and the places moving the other way in which cities have become less diverse since 2000. Full lists are at most diverse states.

Sources

The diversity score is a Simpson diversity index computed by CensusEasy over five race and Hispanic-origin shares, scaled to 0 to 100, and documented at our methodology page. Current shares come from the 2020-2024 American Community Survey 5-year estimates; 1990 figures come from the Census Bureau's 1990 STF3A files. The 1990 census recorded race and Hispanic origin differently from today, and it offered no option to report more than one race, so scores for that year understate diversity somewhat and comparisons across the two points should be read as direction rather than precision.