PID Guide methodology

The PID Guide was produced by the Dutch Digital Heritage Network’s Persistent Identifiers project and is maintained by the National Library of the Netherlands.

The current version of the PID Guide was released on April 4, 2023. New in this version is the addition of ARKs. The website and positions have been updated. Together with experts from the ARK Alliance (ARK), TU Delft Library (for DataCite DOI), SURF (Handle) and the KB, National Library of the Netherlands (URN:NBN), a list was produced of 25 subjects relevant to choosing a PID system. For each subject, the three PID systems were rated on a five-point scale, ranging from “This system doesn’t support this/isn’t suited to this” (1) to “This system fully supports this/is fully suited to this” (5). The rating was determined collectively by the experts representing the different PID systems.

Five point scale

Next, the 25 subjects were converted into statements. Users of the PID Guide can indicate their agreement or disagreement with each statement on another five-point scale, ranging from “I fully disagree” (1) to “I fully agree” (5). The statement in the example above was: “My PIDs are primarily intended for citation and reference by researchers.”

In most cases, the percentile degree of correspondence between the user’s reply and the expert rating for each PID system is calculated using a distance formula:

correspondence = ( 5 – | expert rating – user reply | ) / 5 * 100

Since 2022, users can indicate for a maximum of five statements that they find extra important for their situation. The correspondence score of those five statements counts double in the final result.

The PID Guide was improved over a number of iterations using both expert and user input. From 2018 onward, the PID Guide has a dedicated web site – this one. We welcome your responses, experiences and feedback. Please contact us at

PID Guide Toolkit

If you would like to build your own PID Guide for a different situation, or with different PID systems, you can download and use the PID Guide Toolkit we developed. The ZIP file contains a HTML page (with JavaScript and CSS) and a manual in English and Dutch. 


The PID Guide and PID Guide Toolkit may be used and distributed according to the CC0 license guidelines. Please note that although the PID Guide is based on general knowledge about PID systems, it was developed with the Dutch cultural heritage situation in mind.