All counties in Ohio
| County Name | Population | State | Rank |
|---|
| Cuyahoga County | 1,280,122 | Ohio | 1 |
| Franklin County | 1,163,414 | Ohio | 2 |
| Hamilton County | 802,374 | Ohio | 3 |
| Summit County | 541,781 | Ohio | 4 |
| Montgomery County | 535,153 | Ohio | 5 |
| Lucas County | 441,815 | Ohio | 6 |
| Stark County | 375,586 | Ohio | 7 |
| Butler County | 368,130 | Ohio | 8 |
| Lorain County | 301,356 | Ohio | 9 |
| Mahoning County | 238,823 | Ohio | 10 |
| Lake County | 230,041 | Ohio | 11 |
| Warren County | 212,693 | Ohio | 12 |
| Trumbull County | 210,312 | Ohio | 13 |
| Clermont County | 197,363 | Ohio | 14 |
| Delaware County | 174,214 | Ohio | 15 |
| Medina County | 172,332 | Ohio | 16 |
| Licking County | 166,492 | Ohio | 17 |
| Greene County | 161,573 | Ohio | 18 |
| Portage County | 161,419 | Ohio | 19 |
| Fairfield County | 146,156 | Ohio | 20 |
| Clark County | 138,333 | Ohio | 21 |
| Wood County | 125,488 | Ohio | 22 |
| Richland County | 124,475 | Ohio | 23 |
| Wayne County | 114,520 | Ohio | 24 |
| Columbiana County | 107,841 | Ohio | 25 |
| Allen County | 106,331 | Ohio | 26 |
| Miami County | 102,506 | Ohio | 27 |
| Ashtabula County | 101,497 | Ohio | 28 |
| Geauga County | 93,389 | Ohio | 29 |
| Tuscarawas County | 92,582 | Ohio | 30 |
| Muskingum County | 86,074 | Ohio | 31 |
| Scioto County | 79,499 | Ohio | 32 |
| Ross County | 78,064 | Ohio | 33 |
| Erie County | 77,079 | Ohio | 34 |
| Hancock County | 74,782 | Ohio | 35 |
| Belmont County | 70,400 | Ohio | 36 |
| Jefferson County | 69,709 | Ohio | 37 |
| Marion County | 66,501 | Ohio | 38 |
| Athens County | 64,757 | Ohio | 39 |
| Lawrence County | 62,450 | Ohio | 40 |
| Washington County | 61,778 | Ohio | 41 |
| Sandusky County | 60,944 | Ohio | 42 |
| Knox County | 60,921 | Ohio | 43 |
| Huron County | 59,626 | Ohio | 44 |
| Seneca County | 56,745 | Ohio | 45 |
| Pickaway County | 55,698 | Ohio | 46 |
| Ashland County | 53,139 | Ohio | 47 |
| Darke County | 52,959 | Ohio | 48 |
| Union County | 52,300 | Ohio | 49 |
| Shelby County | 49,423 | Ohio | 50 |
| Auglaize County | 45,949 | Ohio | 51 |
| Logan County | 45,858 | Ohio | 52 |
| Brown County | 44,846 | Ohio | 53 |
| Crawford County | 43,784 | Ohio | 54 |
| Highland County | 43,589 | Ohio | 55 |
| Madison County | 43,435 | Ohio | 56 |
| Fulton County | 42,698 | Ohio | 57 |
| Holmes County | 42,366 | Ohio | 58 |
| Preble County | 42,270 | Ohio | 59 |
| Clinton County | 42,040 | Ohio | 60 |
| Ottawa County | 41,428 | Ohio | 61 |
| Mercer County | 40,814 | Ohio | 62 |
| Champaign County | 40,097 | Ohio | 63 |
| Guernsey County | 40,087 | Ohio | 64 |
| Defiance County | 39,037 | Ohio | 65 |
| Williams County | 37,642 | Ohio | 66 |
| Coshocton County | 36,901 | Ohio | 67 |
| Perry County | 36,058 | Ohio | 68 |
| Morrow County | 34,827 | Ohio | 69 |
| Putnam County | 34,499 | Ohio | 70 |
| Jackson County | 33,225 | Ohio | 71 |
| Hardin County | 32,058 | Ohio | 72 |
| Gallia County | 30,934 | Ohio | 73 |
| Hocking County | 29,380 | Ohio | 74 |
| Fayette County | 29,030 | Ohio | 75 |
| Carroll County | 28,836 | Ohio | 76 |
| Van Wert County | 28,744 | Ohio | 77 |
| Pike County | 28,709 | Ohio | 78 |
| Adams County | 28,550 | Ohio | 79 |
| Henry County | 28,215 | Ohio | 80 |
| Meigs County | 23,770 | Ohio | 81 |
| Wyandot County | 22,615 | Ohio | 82 |
| Paulding County | 19,614 | Ohio | 83 |
| Harrison County | 15,864 | Ohio | 84 |
| Morgan County | 15,054 | Ohio | 85 |
| Noble County | 14,645 | Ohio | 86 |
| Monroe County | 14,642 | Ohio | 87 |
| Vinton County | 13,435 | Ohio | 88 |