Census Data for Oak Brook
Population ...
The most recent Census Estimate<1> was for 2019 and it gave Oak Brook a population of 8,079 people.
The last Decennial Census<2> was in 2010, which gave Oak Brook a population of 7,883 people.
The village of Oak Brook is located in DuPage County. The 2010 Census gave DuPage County; a population of 916,924 people. This means that Oak Brook had 0.86% of the county's total population, making it DuPage's 28th most populous community.
At the same time, Illinois had a population of 12,830,632 people, meaning that Oak Brook had 0.06% of the total population of Illinois - making it the state's 257th most populous community.
Area ...
The 2010 Census shows that the sampling area for Oak Brook has a total area of 8.28 square miles [21.4 km²]. Of this total, 7.95 square miles [20.6 km²] is land, with the balance (3.97%) being water (0.33 square miles [0.9 km²]).
DuPage County has a land area of 327.5 square miles [848.2 km²]. At 7.95 square miles [20.6 km²], Oak Brook has 2.43% of the county's total land area.
- Continue Reading ...
- When the Census Bureau conducts a census for a village like Oak Brook, they draw a boundary around the area in which they are going to conduct their count - this defines the sampling area (usually a polygon). The shape of the sampling area can be quite complex and it's important to keep in mind that the boundaries of the sampling area may or may not match the recognized boundaries of the village.
- Things like population, area and housing for Oak Brook reflect the sampling area. Since the shape of the sampling area and the actual boundaries of Oak Brook might be different, it's best to check with the U.S. Census Bureau to resolve any difference between the two.
- Not only does the sampling area define boundaries, it also has a GPS location (latitude & longitude) that indicates a point within the sampling area (usually the center of the polygon, known as the centroid). At the time of the 2010 Census, the sampling area was located at:
- Lat: 41° 50' 11" (or 41.84°)
- Lon: -87° 57' 12" (or -87.95°)
- More information on this topic and the changes between the 2000 Census and the 2010 Census can be found in the section for our Census-to-Census Observations ... (see below).
Housing Units ...
At the time of the 2010 Census, Oak Brook had 3,188 Housing Units<3> and with its population of 7,883 people, this averages 2.47 people per Housing Unit.
- Continue Reading ...
- The 2010 Census shows Oak Brook had a land area of 7.95 square miles [20.6 km²]. This translates to 385.1 Housing Units per square mile [148.7 housing units/km²].
- From the Census of 2000: Oak Brook had 3,258 Housing Units, a population of 8,702 people and a land area of 8.16 square miles [21.1 km²]. This gives a density of 2.67 people per Housing Unit and 394.6 Housing Units per square mile [152.3 housing units/km²].
- Note: Repeating the caution above (under Population Density), be aware that when comparing Housing Units between the 2010 Census and the 2000 Census, there were changes in the sampling area for Oak Brook and you need to be careful when comparing results between the censuses. More information about the changes can be found in the section called Census-to-Census Observations ... (see below).
DuPage County ...
The community of Oak Brook is primarily located in DuPage County<4>. A portion of Oak Brook extends into Cook County.
The county had a population of 916,924 people at the 2010 Census. With it's population of 7,883 people, Oak Brook represented 0.86% of the county's total.
In addition, where the village of Oak Brook has a population density of 952 people per square mile [367.7 people/km²], DuPage County averages 2,799 people per square mile [1,080 people/km²].
For more information, please visit our Census Page for DuPage County.
Census-to-Census Observations ...
Introduction ...
When the Census Bureau takes a census count (or enumeration) for Oak Brook, they start by specifying the boundaries of the area to be counted. This area (or sampling area) is a polygon and its shape can be quite complex - it may or may not match the geographical boundaries of Oak Brook. It's important to note that from one Census to the next, the shape and location of the polygon can change.
- Continue Reading ...
- Although we don't have specific information about the shape of the polygon for Oak Brook or how it changed has over time, there is some information that can give us some hints. For example, since the shape of the sampling area is directly related to the shape of the polygon, any change to area probably indicates a new shape for the polygon.
- If you need precision or details about the methodology of the Census, you should visit the U.S. Census Bureau for a definitive answer.
Location ...
While generally coinciding with the GPS location (latitude/longitude) of Oak Brook, the latitude and longitude given by the Census Bureau actually indicates the GPS location of the polygon for Oak Brook.
- Continue Reading ...
- For the 2010 Census, the location was given as:
- Lat: 41.836610° (or 41°50'11" N)
- Lon: -87.953472° (or -87°57'12" W)
- For the 2000 Census, the location given was:
- Lat: 41.840180° (or 41°50'24" N)
- Lon: -87.953079° (or -87°57'11" W)
- The difference indicates that the U.S. Census Bureau moved the location of the polygon for the 2010 Census 1,305 feet to the south<5> of the location that was used in the 2000 Census.
- The U.S. Geological Survey (USGS) and the U.S. Board on Geographic Names (BGN) have assigned a unique GNIS identifier (#2399533) to Oak Brook. This identifier also marks a GPS point on the map, and that point lies within the boundaries of Oak Brook. The GNIS point has been mapped to the latitude/longitude:
- Lat: 41.837210° (or 41°50'13" N)
- Lon: -87.951363° (or -87°57'4" W)
- The GPS location given for the 2010 Census lies 613 feet to the west<6> of the point given by the GNIS for Oak Brook. For more information about this and the relationship of the various Federal Codes, please visit our Misc Page for Oak Brook.
Miscellaneous Information for Oak Brook ...
The Federal government has assigned various identifying codes to each community, county and state. At one time or another, the US Census Bureau has used one (or more) of the following identifiers when referring to either DuPage County or the village of Oak Brook:
- The GNIS Codes ...
- The FIPS Codes ...
- An earlier (and largely obsolete) identification method was called the Federal Information Processing Standard (FIPS):
- State Code: 17 (Illinois)
- County Code: 043 (DuPage County)
- Place Code: 54534 (Oak Brook)
- State & County Code: 17/043 (Illinois / DuPage County)
- State & Place Code: 17/54534 (Illinois / Oak Brook)
- Misc. Census Codes ...
- Oak Brook is located in Census Region #2 (the Midwest Region) and Division #3 (the East North-Central Division).
- The US Postal Service ZIP Code ...
- While some people have used a ZIP code to identify a community, the purpose of the ZIP code was to make mail delivery more efficient by grouping addresses together. Although the ZIP Code doesn't specifically identify a village like Oak Brook, it does identify addresses that are in (or near) Oak Brook. It's important to remember that the boundaries of a ZIP Code can be changed, re-assigned or overlapped with other ZIP Codes.
- The ZIP code for Oak Brook:60523<7>
- Census ZCTA Codes ...
- The US Census Bureau created statistical entities that they call ZIP Code Tabulation Areas (ZCTAs) and these ZCTAs are frequently confused with the ZIP codes that come from the US Postal Service (USPS).
- ZCTAs were first created for the 2000 Census and at that time, they were based upon the USPS ZIP codes. While largely covering the same areas, the boundaries of a ZCTA do not necessarily match the boundaries of a postal ZIP code with the same number. For example, while a postal ZIP code can cross a county or state line, a Census ZCTA can not. They should be treated as separate entities with no correlation between them.
For more information about the various Federal identification codes, please visit our Misc Page for Oak Brook.
Off-the-Road Links ...
The official website for Oak Brook: www.oak-brook.org/
The official website for DuPage County: www.dupageco.org/
The official website for State of Illinois: https://illinois.gov
The official website of the U.S. Census Bureau
The official website of the U.S. Board on Geographic Names (BGN)
The official website of the U.S. Geological Survey (USGS)
Footnotes ...
| <1> | Every year, the US Census Bureau creates a population estimate for the preceeding year. Keep in mind that this value is an estimate and not an actual count. The most recent Census estimate is for the year 2019. |
| <2> | Every 10 years (eg- 1990, 2000, 2010), the US Census Bureau conducts a Constitutionally-mandated count (or enumeration) of people living within the United States. This count is called a Decennial Census. The last Decennial Census was the 2010 Census, with the next one planned for 2020. |
| <3> | A Housing Unit is a broad term for those places where people live (whether occupied or temporarily vacant), such as a house, an apartment, a mobile home, or an area that is considered as a separate living quarter. Separate living quarters (consisting of one or more rooms) are considered to be those places where people live, sleep and eat separately from others and that have access to the outside (either directly or by a shared hallway). |
| <4> | If you're interested in how the shape of Illinois' counties, including DuPage, have changed over time, we recommend the Atlas of Historical County Boundaries. |
| <5> | The calculated bearing (or angle) to the 2010 Census location is 175 degrees and a distance of 1,305 feet. |
| <6> | The calculated bearing (or angle) to the GNIS point is 110 degrees and a distance of 613 feet. |
| <7> | When looking for a ZIP Code, whether Oak Brook or elsewhere, it's always best to check the website of the United States Postal Service (USPS). |