Rockdale County area

Population and density of Rockdale County

The Census Bureau estimates that 98,416 people lived in Rockdale County on July 1, 2025. That ranks #640 of 3,222 county equivalents nationally and #30 of 159 in Georgia. Since the April 1, 2020 estimates base of 93,487, the population has grown by 4,929 (+5.3%), compared with +5.5% for Georgia as a whole.

With 129.8 square miles of land, that is 758 people per square mile (293 per km²), placing Rockdale County #242 nationally for density and #11 in Georgia. The median county equivalent has 47 people per square mile; the Georgia median is 69. Put another way, there are about 0.844 acres of land per resident.

U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.

Cities and towns in Rockdale County

1 incorporated place lies at least partly in Rockdale County. Together they are home to 20,377 people (20.7%); the other 78,039 (79.3%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Conyers city, with 20,377 residents in the county.

Metropolitan area

Rockdale County is a central county of the Atlanta-Sandy Springs-Roswell, GA Metropolitan Statistical Area, in the Atlanta-Sandy Springs-Roswell, GA metropolitan division. Its 29 county equivalents have 6,482,182 residents on 8,784.1 square miles of land; Rockdale County accounts for 1.5% of the land and 1.5% of the residents. By combined land it ranks #10 of 393 metropolitan areas, and #6 by population. It belongs to the Atlanta--Athens-Clarke County--Sandy Springs, GA-AL Combined Statistical Area.

ZIP codes

9 ZIP Code Tabulation Areas have land in Rockdale County; 3 of them have most of their land inside the county, and the others mainly cover neighboring areas.

300123001330016300523005830094302523028130294

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Rockdale County

Rockdale County shares a land border with 5 county equivalents. Each of them has more land than Rockdale County. The largest neighbor is Gwinnett County (431.2 mi²) and the smallest is DeKalb County (267.6 mi²). Together with its neighbors, Rockdale County forms a block of 1,748 mi² of land, of which it holds 7.4%.

How big is Rockdale County compared with U.S. states?

Rockdale County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 8 times as much. Georgia’s county land could hold about 445 areas the size of Rockdale County.

Another way to picture it: the same land area would fill a square about 11.4 miles (18.3 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.

State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.

What stands out about Rockdale County?

Rockdale County has more land than 148 of the other 3,221 county equivalents in the dataset.

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places Rockdale County at #3,092 nationally by total area, 18 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 1.7%, compared with a national county-equivalent median of 1.2% — 0.6 percentage points higher. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside Rockdale County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.