DOI (Digital Object Identifier)

A unique alphanumeric string assigned to identify digital content such as journal articles, research reports, and datasets. DOIs provide a permanent link to content even if the URL changes.

Why it matters

DOIs ensure that citations remain valid even when publishers move content to new URLs. Including a DOI in your reference list makes it easy for readers and reviewers to locate the exact source you used, which strengthens the credibility of your work.

How to use

When citing a source that has a DOI, include it at the end of your reference entry formatted as a URL (e.g., https://doi.org/10.1000/xyz123). Most citation styles now prefer the URL format over the older "doi:" prefix. You can look up a DOI on doi.org to verify it resolves to the correct article.

In academic writing

Students encounter DOIs most frequently when citing journal articles, conference papers, and datasets from academic databases like JSTOR, PubMed, or Google Scholar. Many professors and journals require DOIs in reference lists because they guarantee permanent access to the cited work.