County Data

American Community Survey Profiles
Single Year Estimates
The following are general profiles of counties with populations over 65,000, including information on population and housing:
County Population Estimates
Top Ten Counties by Population
County July 1, 2012 Population Estimate
Johnson 559,913
Sedgewick 503,889
Shawnee 178,991
Wyandotte 159,129
Douglas 112,864
Leavenworth 77,739
Riley 75,508
Butler 65,827
Reno 64,439
Saline 55,988

County Population Projections
The Center for Economic Development and Business Research at Wichita State University has created the following projections by Kansas County by age for 2000-2030:
Historic Census Data
This table shows the decennial Census count of the state and current counties from 1900-2010. The following table includes the decennial count for the state and counties, including historic county names in use at the time of the Census. Finally, these are the notes from the 1920 Decennial Census that explain the name and boundary changes to counties between 1860 and 1920.

County QuickFacts
The US Census Bureau's QuickFacts page provides the most recent information on the State, Counties and about 50 cities. You can access QuickFacts online, then use the drop down menu to find the county you are interested in.