Getting started

ARKs – popular and easy to use

The Archival Resource Keys (ARKs) are identifiers dedicated to link in a persistent manner to resources of all types – digitized documents and objects, (scientific) publications, genealogical records, museum specimens, educational resources, authors and scholars, and even abstract concepts.

The ARK’s main objective is to provide identifiers tailored to the needs of data producers on the web and designed to ensure continuous access to the information in question. Its success is no surprise: more than 500 registered organizations have created at least 3.2 billion ARKs. They are found in the digital collections of the National Library of Luxembourg (BnL), in Wikipedia articles and Wikidata entries, and in the collections of the Internet Archive. In the near future, the National Archives (ANLux) will also adopt the ARK format.

How to ensure permanent access to information?

The Resolver

A persistent identifier is supposed to work, even if the resources to which it refers to were moved from one website to another. In this context, the resolver comes into play. It is a website specialized in redirecting incoming identifiers to sites currently operating. The website serves as a resolver for ARKs assigned to organizations based in Luxembourg. This redirecting process will only work, if the institutions authorized to assign ARKs ensure the maintenance of their URLs and notify the resolver of any changes.

The ARKs introduce themselves

In short, the ARKs base themselves on the following principles


ARKs ensure persistent access to digital information. You cannot modify or reassign an ARK. Its stability is guaranteed, even if the referenced resources are moved from one website to another or when the managing organization changes its name.


No ARK identifier will be assigned anew: once a link between an ARK identifier and an object has been published, it is to be considered unique for an indefinite period of time. Even if a resource has been deleted, it is essential that a published ARK continues to point, if not to the resource itself, then at least to its metadata and to a reference indicating the cause of its inaccessibility. In addition, a user may be granted access to a substitute resource.


Optionally, ARKs are “talkative”: they provide access to metadata about the resource and/or to a declaration of permanence (a commitment by the organization detailing the dissemination period and the mode of distribution).


ARKs favors the citability of a link, that is, the ability of a user to name and locate a resource. Using ARKs you can reference resources in publications (digital or even on paper), scientific articles, web pages or simply in bookmarks of web browsers, without having to modify these links each time a referenced resource changes its access URL.


The strings of characters that refer to an ARK are generally “opaque” (meaningless) and deliberately reveal little information about the resource in question. This helps avoid the temptation to change a resource’s identifier, if some of its characteristics change. However, depending on the user’s needs, “meaningful” strings can be generated.

Wide scope of application

The allocation process is simple and the scope of application wide. You can assign an ARK to all types of resources.