We have written an example reference client implementation for using our API via the JSON-REST endpoint for PHP: PostcodeNl_Api_RestClient.
We will take care never to break existing fields or behavior without warning. Please note that we reserve the right to add new fields to responses in the future, so your client should ignore future unknown fields at any depth in the response.
HTTP Basic authentication is used, with the values of your applications Key and Secret used as username and password, respectively. You can obtain a Key and Secret by registering an application account.
Parameter values are added to the method URL according to the documented method URL template, and each parameter must be url-encoded.
Address API methods
- Dutch address lookup by postcode
- Dutch address lookup by city, street and housenumber
- Dutch address lookup by Rijksdriehoeksmeting coordinates
- Dutch address lookup by latitude and longitude
- Dutch postcode range lookup by postcode
Frequently Asked Questions
Should I use GET or POST?
The Address REST API requires GET requests.
Why do I receive a 404 error if the address is not found?
We use HTTP Status codes to classify success or error reasons.
- 200 OK
- Positive result found.
- 404 Not found
- No result found, address does not exist, etc.
- 400 Bad request
- Missing or invalid parameters. This often indicates a request which could've been prevented by doing client side parameter syntax checks first.
- 401 Unauthorized
- Missing, invalid or disabled credentials.
- 409 Conflict
- Only relevant for the exact search, see the method documentation.
Browser clients and jsonp support
own server instead of making cross domain calls directly in the browser. This proxy script would hold the key and secret: It is not allowed to
You're responsible for keeping the secret safe.
I am getting a warning about SSLv3 when connecting
Our services are only available using safe HTTPS implementations. We do not support the older SSL(v3) protocol when communicating over HTTPS, instead use the more secure TLS protocol (v1.0-v1.2). Most internet communication libraries will support TLS automatically.