Open Archives API

This documentation describes version 1.0 of the Open Archives API. The methods marked with an asterisk (*) require an API key, contact Open Archives to apply for one. All output is in UTF-8 and cached (server-side and via max-age header) for a day, unless otherwise specified.

API calls are throttled per IP address to 4 requests per second (Leaky Bucket).


  • Search - searches the genealogical data set and returns the found persons (and records)
  • Match - searches for records where a person identified by name and birthyear is mentioned
  • Show - shows one specific genealogical record
  • Years ago - lists people born years ago


  • Add (*) - adds a comment to a record
  • Delete (*) - deletes a comment
  • List - lists comments made on records



  • Weather - historical weather measurements
  • Census - information about the Dutch population
Postman webview

Open Archives URI

Records presented on Open Archives all have an URI. This URI resolves to content based on content-negotiation.

File exports

Open Archives shares all the data in downloadable file exports (in CSV and A2A).

Open Search

Open Archives provides search results as defined by the Open Search specification. There's an OpenSearch description docu­ment for each language: NL, EN, DE & FR.

Want to harvest the genealogical data?

Open Archives also provides an OAI-PMH data provider for harvesting.

Find your ancestors and publish your family tree on Genealogy Online via