Constructing your DOIs

Crossref DOIs are structured like this:

The structure of a DOI: resolver, prefix, suffix

As you can see, it has several parts:

  • = the DOI resolver: makes the DOI a URL (actionable)
  • 10.5555 = prefix: assigned by Crossref
  • YFRU1371 = suffix: decided and assigned by the member, should be opaque.

The prefix and suffix together make a DOI, and with the DOI resolver they form a DOI link.

The DOI link uses the DOI resolver system to look up the registered URL for the item. This shows why it’s important to keep the metadata up-to-date, so that the DOI always points to the correct URL for the item.

When you join Crossref as a member, we assign you a DOI prefix, and you then create your own suffixes when you register your content and its associated metadata.

We don’t provide your DOIs for you. If you’re using the Crossref XML plugin for OJS, the plugin will generate your suffixes for you automatically. For other content registration methods, you’ll either decide your own suffix pattern, or make use of our suffix generator. Either way, it’s important that your suffixes are opaque.

The importance of opaque identifiers

As a DOI is a persistent identifier, the DOI string can’t be changed after it’s been registered. It’s therefore important that your DOI string is opaque and doesn’t include any human-readable information. This means that the suffix should just be a random collection of characters. It should not include any information about the work that could be changed in the future, to avoid a difference between the information in the DOI string, and the information in the metadata.

For example, 10.5555/njevzkkwu4i7g is opaque (and correct), but 10.5555/ogs.2016.59.1.1 is not opaque (and not correct); it encodes information about the publication name and date which may change in the future and become confusing or misleading. So don’t include information such as publication name initials, date, ISSN, issue, or page numbers in your suffix string.

Tips for creating a DOI suffix

  • Get help: Try our suggested DOI registration workflow, including our suffix generator.
  • Be concise: Make the suffix short and easy to read. Remember, DOIs will appear online and in print; users will also re-type DOIs.
  • Be unique: A suffix must be unique within your prefix.
  • Be case insensitive: A suffix is case insensitive, so 10.1006/abc is the same as 10.1006/ABC.
  • Be consistent: The suffix should reflect a consistent, logical system that can be easily recorded and understood by employees of your organization. For example, you might want the suffix to include existing internal identifiers or an ISBN.
  • Keep it opaque: don’t include any specific of descriptive information in the DOI - that information is included in the metadata you supply. If you add bibliographic information in a DOI string it will have no meaning within our system nor the DOI system so will be confusing. Avoid page numbers in particular - choosing a pattern that is linked to page numbers makes it difficult to put content online before pagination is complete for a print version, or if the items are published online only.
  • Only use approved characters: Your DOI suffix can be any alphanumeric string, using the approved characters “a-z”, “A-Z”, “0-9” and “-._;()/” You might see some older (pre-2008) DOIs which contain other characters. Learn more about suffixes containing special characters.
  • Make suffixes extensible: DOI suffixes should be extensible, to allow DOIs to be assigned to parts of a content item, such as figures, graphs, and supplementary materials. In an example article with DOI 10.1006/jmbi.1998.2354, the second figure in the article might be assigned this DOI: 10.1006/jmbi.1998.2354.f002
  • Work with your repository handle: we have specific advice if you’re registering original, non-duplicative published content in a repository. Read more about advice for DOIs and DSpace repositories.

Example DOI suffix patterns

Crossref member Example DOI
American Astronomical Society 10.1086/323445
American Institute of Physics 10.1063/1.125173
American Chemical Society 10.1021/cm960127g
CSHL Press 10.1101/gr.10.12.1841
IEEE 10.1109/16.8842
Oxford University Press 10.1162/003355397555109
UChicago Press 10.1086/301055

What if your content already has a DOI?

Sometimes members may acquire a journal that already has DOIs registered for some articles. It’s important to keep and continue to use the DOIs that have already been registered and not change them - DOIs need to be persistent.

It doesn’t matter if the prefix on the existing DOI is different from the prefix belonging to the acquiring member. As content can move between members, the owner of a DOI is not necessarily the same as the owner of the prefix. Read more about transferring responsibility for DOIs.

Page owner: Isaac Farley   |   Last updated 2020-October-06