A clear way to identify your publication
Different publications can have similar titles or creator names. Web links can also change. An SPSN points to one specific publication and format, so people can tell exactly which one you mean.
You can show the number inside the publication, on its website, in a catalogue or wherever you share its details. Anyone can then look it up and check the public page.
Made for independent publishing
You can apply as an individual, self-publisher, independent publisher, small press or organisation. Each application costs USD 7 and is reviewed by a person before a number is issued.
Use it alongside other numbers
A publication can have both an SPSN and an ISBN, DOI, ISSN or ISMN. You can add those existing numbers to its SPSN page so readers and organisations can see them together.