Postcode Lookup Online
Look up postal codes in 124 countries (place, state, county, coordinates), search by place or nearest point, validate formats of 180 countries.
Result
Press “Run” to see the result.
country + postcode (or /v1/world-postcodes/<CC>/<code>) returns the places that use the code with their first, second and third-level divisions and approximate coordinates; spaces, dashes and case do not matter (sw1a1aa = SW1A 1AA). A partial code (an outward code such as SW1A, the first digits of a ZIP) lists the codes that start with it. Every answer also says whether the code matches the official format of the country (format.valid, the pattern and examples); validate_only=true checks the format without a lookup, and works for about 180 countries – including those without a database, such as Vietnam.
q finds places by name in a country (accents optional) with their codes; lat + lon returns the nearest postal codes to a point. action=countries lists the countries covered and action=formats the format patterns.
Data: the GeoNames postal-code dump (CC BY 4.0, refreshed weekly) – about 4.1 million codes; the UK and the Netherlands have full codes (UK from Code-Point Open, Open Government Licence), Canada, Ireland, Malta, Chile and Argentina only the first part, Brazil only major codes, and some countries (Vietnam included) none. Coordinates are centroids, not delivery points. Formats come from Google's address metadata (libaddressinput, CC BY 4.0). Keep the attribution text when you display the data.
Use this in your code
curl "https://apibox.io.vn/v1/world-postcodes?country=GB&postcode=sw1a1aa" \
-H "Authorization: Bearer YOUR_API_KEY"const res = await fetch('https://apibox.io.vn/v1/world-postcodes?country=GB&postcode=sw1a1aa', {
method: 'GET',
headers: {
Authorization: 'Bearer YOUR_API_KEY',
},
});
const data = await res.json();
console.log(data);import requests
res = requests.get(
"https://apibox.io.vn/v1/world-postcodes?country=GB&postcode=sw1a1aa",
headers={"Authorization": "Bearer YOUR_API_KEY"},
timeout=30,
)
print(res.json())<?php
$ch = curl_init('https://apibox.io.vn/v1/world-postcodes?country=GB&postcode=sw1a1aa');
curl_setopt_array($ch, [
CURLOPT_RETURNTRANSFER => true,
CURLOPT_HTTPHEADER => ['Authorization: Bearer YOUR_API_KEY'],
]);
$response = curl_exec($ch);
print_r(json_decode($response, true));API documentation → Get a free API key
FAQ
Which countries are covered?
124 countries have a database (action=countries lists them with their row counts); about 180 have a format check. Vietnam has format validation here and its own lookup at /v1/vn-postcode.
Why does a Canadian code only give the first three characters?
Full Canadian postal codes are Canada Post's property; the open data only has the forward sortation area (e.g. K1A). Use those three characters for the lookup.
Are the coordinates exact?
No. They are centroids of the code area or of the place; the accuracy field (1, 4 or 6) tells how they were obtained.