PostcodeData.nl API

Overview

Measurement Record

What actually happened when we called this API from our own infrastructure. Every value below was recorded by the request, not copied from the provider's documentation.

Request

GET http://api.postcodedata.nl/v1/postcode/?postcode=1211EP&streetnumber=60&ref=test&type=json

Result

HTTP 200 · application/json · 299 bytes

Response time

494 ms (median of 3) · fastest 361 ms

Browser CORS

Allowed — Access-Control-Allow-Origin: *

Served by

Apache/2.4.25 (Ubuntu)

Recorded

2026-08-10

Fields Returned

Top-level fields present in the response we captured, with the type and value we actually received.

Captured Response

Captured from a real request to http://api.postcodedata.nl/v1/postcode/?postcode=1211EP&streetnumber=60&ref=test&type=json on 2026-08-10. Long arrays and nested objects are truncated to keep the shape readable.

{
  "status": "ok",
  "details": [
    {
      "street": "Stationsstraat",
      "city": "Hilversum",
      "municipality": "Hilversum",
      "province": "Noord-Holland",
      "postcode": "1211 EP",
      "pnum": "1211",
      "pchar": "EP",
      "rd_x": "140707.47566666666666666667",
      "rd_y": "471005.06166666666666666667",
      "lat": "52.2269378842251",
      "lon": "5.1780191356884"
    }
  ]
}

Implementation Example

Request skeleton. The URL below is this API's documentation page, not a live endpoint — swap in the path you need from the provider's docs before running it.

const url = "http://api.postcodedata.nl/v1/postcode/";
const response = await fetch(url);
if (!response.ok) throw new Error(`Request failed: ${response.status}`);
const data = await response.json();
console.log(data);

import requests

url = "http://api.postcodedata.nl/v1/postcode/"
headers = {}

response = requests.get(url, headers=headers, timeout=30)
response.raise_for_status()
data = response.json()
print(data)

curl "http://api.postcodedata.nl/v1/postcode/?postcode=1211EP&streetnumber=60&ref=test&type=json"

What Can You Build?

// Geocode an address to latitude/longitude
const address = '1600 Amphitheatre Parkway, Mountain View, CA';
const response = await fetch(`http://api.postcodedata.nl/v1/postcode/?postcode=1211EP&streetnumber=60&ref=domeinnaam.nl&type=json`);
const data = await response.json();
const location = data.results?.[0] || data;
console.log('Latitude:', location.lat || location.latitude);
console.log('Longitude:', location.lon || location.longitude);

// Get location from IP address
const response = await fetch(`http://api.postcodedata.nl/v1/postcode/?postcode=1211EP&streetnumber=60&ref=domeinnaam.nl&type=json`);
const data = await response.json();
console.log('Country:', data.country || data.country_name);
console.log('City:', data.city);
console.log('Coordinates:', data.lat || data.latitude, data.lon || data.longitude);

// Get coordinates and calculate distance
const response = await fetch(`http://api.postcodedata.nl/v1/postcode/?postcode=1211EP&streetnumber=60&ref=domeinnaam.nl&type=json`);
const data = await response.json();
const loc = data.results?.[0] || data;
const lat1 = loc.lat || loc.latitude || 0;
const lon1 = loc.lon || loc.longitude || 0;
// Haversine distance formula
const R = 6371;
console.log(`Location: ${lat1}, ${lon1}`);

Note: These code examples are AI-generated and unverified. Always refer to the official API documentation for accurate usage.

How This API Fails

We deliberately sent this API a broken request and recorded exactly what came back on 2026-08-10. Knowing the shape of an error before you hit it makes error handling much easier to write.

Common Errors & Troubleshooting

Generated guidance based on this API's documentation, not observed by us. Treat it as a starting point and check against the provider's own error reference.