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What ZIP Code Am I In?

ZIP codes are postal routes, not areas, so a phone will not show one. This tool geocodes your position and returns the ZIP the Postal Service assigns to it.

How to use it

  1. Tap "Use my location" and allow location access, or type an address, or click the map.
  2. Read the five-digit ZIP, the city and state it belongs to, its population and the county it falls in.
  3. If the geocoder has no ZIP for the exact point, the nearest ZIP area is shown and labelled as approximate.

How it works

The position is reverse-geocoded by Nominatim, the OpenStreetMap geocoder, which returns the postal code recorded for the nearest address. The ZIP is then matched to its Census ZIP Code Tabulation Area (ZCTA) from the 2025 Gazetteer for the city, state and centre point, with population from the ACS 2020-2024 five-year estimate.

The county is looked up separately from the Census 2020 boundary through the FCC Area API, because a ZIP can cross county lines.

Postal ZIP codes are delivery routes and have no official boundary. ZCTAs are the Census Bureau's approximation of them, so in rural areas and at the edge of a route the ZIP the Postal Service uses can differ from the ZCTA returned here. Post-office-box ZIPs have no area at all.

Questions

What ZIP code am I in right now?
Allow location access and the ZIP recorded for the nearest address is shown, with the city and county. On a desktop, where the browser location can be miles off, type your street address instead.
Why is the ZIP different from the one on my mail?
The tool returns the postal code recorded in OpenStreetMap for the address nearest your position. Where a ZIP boundary runs between neighbours, or in a large rural route, the record can be one ZIP off. The Postal Service address lookup is the final word.
What is a ZCTA?
A ZIP Code Tabulation Area is the Census Bureau's area version of a ZIP code, built from census blocks so that population can be counted for it. It usually matches the ZIP closely but not exactly.

All map tools, free and without an account. Location data is processed in your browser and by the open geocoding services named on the sources page; nothing is stored by this site.