About CountyAtlas

CountyAtlas maps and publishes official data for every U.S. county and county-equivalent: population, income, unemployment, land area, and county seats. It also has free tools to find your county, city, state, and congressional district. Every figure traces to a primary source, and anything a source can’t confirm is left blank rather than guessed.

Who runs CountyAtlas

CountyAtlas is built and maintained by Marko Visic (BSc Physics, University of Ljubljana). Physics trains you to work carefully with primary data: measure, state the uncertainty, and refuse to report a number the evidence doesn’t support. CountyAtlas applies the same discipline to public U.S. data. Every figure is traced to an official source with its vintage recorded, and anything unreliable is left out rather than guessed.

Marko Visic’s profile: LinkedIn.

CountyAtlas is operated by Moving Data Systems d.o.o., an independent company based in Slovenia. It has no sponsors, clients, or paid data partners that could influence what the numbers say. It is a reference built to be correct and citable.

What CountyAtlas is

A reference site for U.S. county geography and statistics. For each state it publishes an interactive, color-by-any-measure county map, a sortable data table of every county, print-ready map downloads, and answers to the questions people search for: how many counties a state has, which county is the richest or most populous, and where a given city or address falls. The location tools answer “what county / city / state / congressional district am I in?” from a point on the map or a typed place.

Why you can trust the data

Every number on CountyAtlas comes from an official primary source, and each carries the vintage it reflects:

Boundaries and geography: the U.S. Census Bureau’s TIGER/Line (TIGERweb).
Population: the Census Population Estimates Program (PEP).
Income and poverty: the Census Small Area Income & Poverty Estimates (SAIPE).
Age and educational attainment: the Census American Community Survey (ACS), 5-year.
Unemployment: the Bureau of Labor Statistics’ Local Area Unemployment Statistics (LAUS).
ZIP-code areas: the HUD–USPS ZIP Code Crosswalk (public domain), for ZIP-to-county lookups.
County seats: Wikidata (CC0), each validated against a Census place inside its county, with gaps filled from the pages cited in the seat file.

The governing rule is verified or omitted: a value is shown only when a source confirms it, and unreliable estimates (a coefficient of variation ≥ 0.30) are left blank rather than published as a wrong number. The methodology page documents the full sourcing, vintages, and methods, including how CountyAtlas handles the disputed U.S. county count and Connecticut’s planning regions. The complete dataset is available as a free, openly-licensed CSV.

How this site is made

AI tools help draft the text and the code. Every figure comes from the primary sources listed on the methodology page (the dataset’s own sources are on the data page), and an automated check compares the published figures with those sources each time the data is rebuilt. An AI assistant also reads the most-visited pages in a browser, and Marko Visic, the author, reviews what it finds and approves every change.

Independence & funding

CountyAtlas is free to use. It does not currently run advertising and has no paid sponsors or data partners that could shape which figures are shown or how they’re presented. The data comes entirely from the official sources above. If advertising is introduced later it will be disclosed in the privacy policy, and it will not change how the data is sourced or reported.

Contact & corrections

Found a figure that looks wrong, or have a question? Corrections are welcome: email info@countyatlas.org or use the contact page.