Montana counties ranked by the diversity index, the chance that two public school students picked at random from the county belong to different racial or ethnic groups. Counties need at least 3 schools and 1,000 students to qualify. The median ranked county is at 28.1%.
| # | County | State | Diversity index |
|---|---|---|---|
| 1 | Lake County | MT | 61.9% |
| 2 | Hill County | MT | 58.8% |
| 3 | Rosebud County | MT | 58.7% |
| 4 | Blaine County | MT | 50.4% |
| 5 | Roosevelt County | MT | 47.5% |
| 6 | Cascade County | MT | 44.6% |
| 7 | Yellowstone County | MT | 41.8% |
| 8 | Valley County | MT | 40.7% |
| 9 | Glacier County | MT | 38.3% |
| 10 | Sanders County | MT | 30.4% |
| 11 | Gallatin County | MT | 30.0% |
| 12 | Missoula County | MT | 30.0% |
| 13 | Richland County | MT | 29.4% |
| 14 | Big Horn County | MT | 29.2% |
| 15 | Lewis and Clark County | MT | 28.1% |
| 16 | Silver Bow County | MT | 26.9% |
| 17 | Ravalli County | MT | 24.9% |
| 18 | Deer Lodge County | MT | 24.8% |
| 19 | Lincoln County | MT | 23.2% |
| 20 | Custer County | MT | 22.8% |
| 21 | Flathead County | MT | 21.9% |
| 22 | Dawson County | MT | 21.8% |
| 23 | Park County | MT | 21.5% |
| 24 | Beaverhead County | MT | 21.3% |
| 25 | Stillwater County | MT | 18.3% |
| 26 | Jefferson County | MT | 17.3% |
| 27 | Teton County | MT | 16.8% |
| 28 | Fergus County | MT | 16.6% |
| 29 | Carbon County | MT | 15.3% |