The complete dataset
3,222 records covering the 50 states, District of Columbia, and Puerto Rico. Source: 2026 Census Gazetteer, retrieved September 27, 2026.
What is included?
- Five-digit Census GEOID, official county-equivalent name, state name and abbreviation.
- Original ALAND and AWATER measurements in square meters, plus Census-published square miles.
- Total square miles, calculated by adding the published land and water figures.
- National and state land rankings, calculated from original square-meter values.
- Representative latitude and longitude; these are internal points, not boundary coordinates.
Spreadsheet tip: import GEOID as text so leading zeros are preserved. A GEOID such as 01001 must remain five characters. JSON preserves these identifiers as strings.
Data dictionary: the columns in your download
The CSV contains one row per county equivalent and the fields below, in this order. The JSON contains a counties array plus source metadata and definitions; its records also include slug and stateSlug for constructing profile links. Area fields are numbers, while identifiers remain strings.
| Field | Type / unit | Meaning and use |
|---|---|---|
geoid | Five-character text | County-level identifier, including the two-digit state code. Preserve leading zeros. |
name | Text | Official county-equivalent name, including designations such as parish, city, or municipio. |
state | Text | State, district, or territory name. Use alongside county names in reader-facing tables. |
stateCode | Two-character text | USPS abbreviation, such as TX, DC, or PR. |
landSqM | Integer m² | Original Census ALAND. This is the field used for exact land rankings. |
waterSqM | Integer m² | Original Census AWATER. Add to ALAND to reproduce the total-area ordering. |
landSqMi | mi² | Census-published land square miles, retaining three-decimal source precision. |
waterSqMi | mi² | Census-published water square miles. A rounded zero can mask a positive square-meter value. |
totalSqMi | mi² | Land plus water square miles, rounded to three decimals. |
nationalLandRank | Integer position | Descending original land area across all records. Exact ties sort by GEOID ascending. |
stateLandRank | Integer position | The same land ordering within the state-level jurisdiction. |
latitude | Decimal degrees | Census internal-point latitude; not a boundary, an address, or necessarily a county seat. |
longitude | Decimal degrees | Census internal-point longitude. Do not interpret this point as the county’s extent. |
A reliable first import
- Use your spreadsheet’s CSV import command and explicitly set
geoidto text. Check that01001still has five characters. - Confirm 3,222 records excluding the header and one record per GEOID. Keep the original download before changing any values.
- Sort the entire table by
landSqMdescending andgeoidascending to reproduce national land order. Sorting only one column would detach numbers from their counties. - Calculate water share as
waterSqMi / totalSqMiand format the result as a percentage. Do not multiply by 100 as well as applying percentage formatting.
Filtering to a state does not recalculate nationalLandRank; use stateLandRank for that comparison. For a custom subset, compute and label a new rank. The complete spreadsheet workflow includes spot checks, tie handling, and join diagnostics.
Before combining this with another dataset
Match the geographic level and boundary vintage as well as the identifier. Population and housing counts are not included in the Gazetteer or this download. Obtain those from an appropriate source and check compatibility before calculating a rate. Connecticut’s current planning regions, for example, cannot simply inherit the population of similarly located historical counties.
A county-level average does not describe every neighborhood, and an internal coordinate is not a geocoding service. Read the density denominator guide before joining population, and use suitable detailed boundary data for spatial analysis. These are separate tasks from comparing the official area fields.
Suggested citation
For the underlying measurements, cite the Census Bureau. If you use our rankings or conversions, cite US County Area as the transformation source too.
U.S. Census Bureau. 2026 Gazetteer Files: Counties, national file. Retrieved September 27, 2026. US County Area, county area conversions and rankings, https://uscountyarea.com/.
Measurement definitions and ranking rules · Census Gazetteer documentation ↗
Reuse and limitations
These downloads reorganize publicly available Census measurements and add arithmetic calculations. Attribute the Census Bureau as the original source and retain the vintage when sharing. A ranking is relative to the geography included in this release. These data do not establish legal property boundaries.
Reproducibility
The downloaded Census ZIP had this SHA-256 checksum:
6a99ca00efbc0be5112e225d4102704c51d5ce3b16e3afd6e4159460595fd12aCounty outlines use a separate 2025 cartographic boundary source. They are illustrations and are not used to calculate the 2026 measurements.