Free postal code & ZIP code API
Look up any postal or ZIP code — place, region and coordinates — across 121 countries. No API key, one request.
Why
Postal & ZIP lookup, worldwide
121 countries
1.8 million postal / ZIP codes worldwide, from the open GeoNames dataset.
Place + coordinates
Each code resolves to its place name, admin region and latitude/longitude.
No key, one request
No account or token — GET the code and parse the JSON. Works from the browser.
Quick start
One request, no setup
No keys to generate and nothing to install — call an endpoint and parse the JSON.
Resolve a US ZIP code
curl https://countries.dev/postal/US/10001Any country
curl https://countries.dev/postal/DE/10115Countries with coverage
curl https://countries.dev/postal/countriesIn the browser
const [place] = await fetch('https://countries.dev/postal/US/10001')
.then((r) => r.json());
console.log(place.placeName); // New YorkBrowse postal codes by country (121)
Use it for
What developers build with it
Checkout & shipping
Autofill city and region from a ZIP, validate destinations, estimate zones.
Address forms
Speed up forms — type a postal code, fill in the place and region.
Store locators & enrichment
Geocode a postal code to coordinates for distance and mapping.
Postal code API — FAQ
Is the postal code API free?
Yes — no API key, no sign-up and no quota tier. Use it in production or side projects.
Which countries are covered?
121 countries and roughly 1.8 million postal / ZIP codes, from the open GeoNames dataset. The full list is in the directory below.
What does a lookup return?
The place name, administrative region (and district where available), latitude, longitude and an accuracy level — as JSON.
Does it work for US ZIP codes?
Yes. GET /postal/US/10001 returns New York. The same endpoint resolves codes for every covered country.
Does it validate or autocomplete addresses?
It resolves a known postal code to its place and coordinates. It is not a full address-validation service, but it is ideal for autofilling city/region and geocoding a code.
Do I need an API key?
No. GET the endpoint and parse the JSON; CORS is permissive, so it works from the browser too.
Look up your first postal code
GET countries.dev/postal/US/10001 → place, region and coordinates. The docs cover every covered country.