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What is a DOI?

Everything you need to know about Digital Object Identifiers

🔗 DOI Definition

DOI stands for Digital Object Identifier. It's a permanent link to an online document (usually academic articles, research papers, or datasets) that won't break even if the article moves to a different website.

Think of it like a social security number for research papers - each DOI is unique and permanently identifies one specific document.

📖 What Does a DOI Look Like?

Anatomy of a DOI

10.1234/example.2024.56789
PREFIX
10.1234
Identifies the publisher
SUFFIX
example.2024.56789
Identifies the specific article
Note: All DOIs start with "10." - if you see a number starting with 10., it's probably a DOI!

✨ Real DOI Examples

📄

Journal Article

10.1038/nature12373

A real DOI from Nature journal. The "1038" identifies Nature as the publisher.

🔬

Scientific Study

10.1016/j.cell.2023.10.015

A DOI from Cell Press. The "j.cell" indicates it's from Cell journal, published by Elsevier (1016).

📊

Research Dataset

10.5061/dryad.12345

DOIs aren't just for articles! This one identifies a dataset in the Dryad repository.

🎯 Why DOIs Are Important

✅ Permanent Links

URLs can break or change when websites reorganize. DOIs never change - they always point to the same article.

🔍 Easy to Find

You can search for any DOI at doi.org, and it will take you directly to the article, no matter who published it.

📚 Citation Standard

Academic style guides (APA, MLA, Chicago) require DOIs in citations when available. They're the gold standard.

🌍 Global System

DOIs work internationally across thousands of publishers. One system for the entire research world.

🔍 How to Find a DOI

1. Look at the Top of the Article

Example journal article header:
Journal of Amazing Science
Volume 45, Issue 3, 2024
DOI: 10.1234/jas.2024.0567

Most journal articles display the DOI prominently near the title, author names, or publication date.

2. Check the Article Footer or Sidebar

If not at the top, look at the bottom of the first page or in a sidebar. Common labels include:

  • • "DOI:"
  • • "Digital Object Identifier:"
  • • "https://doi.org/..."
  • • "Article identifier:"

3. Search on Google Scholar or Crossref

If you can't find the DOI on the article itself:

  • Google Scholar: Search for the article title. The DOI often appears in the citation info.
  • Crossref: Visit search.crossref.org and search by title or author.

4. Look in the Database Where You Found It

If you accessed the article through a database (PubMed, JSTOR, EBSCOhost), the DOI is usually displayed in the article details or citation export options.

📝 How to Use DOIs in Citations

Important: Always format DOIs as URLs starting with https://doi.org/

APA 7 Format

Format:

Author, A. A. (Year). Title of article. Journal Name, Volume(Issue), pages. https://doi.org/10.xxxx/xxxxx

Example:

Smith, J. (2024). Climate change effects on coral reefs. Nature, 615, 234-245. https://doi.org/10.1038/nature12373

MLA 9 Format

Format:

Author Last, First. "Title of Article." Journal Name, vol. #, no. #, Year, pp. ##-##, doi:10.xxxx/xxxxx.

Example:

Smith, Jennifer. "Climate Change Effects on Coral Reefs." Nature, vol. 615, 2024, pp. 234-245, doi:10.1038/nature12373.

Chicago Style

Format:

Author Last Name, First Name. "Title of Article." Journal Name Volume, no. Issue (Year): Pages. https://doi.org/10.xxxx/xxxxx.

Example:

Smith, Jennifer. "Climate Change Effects on Coral Reefs." Nature 615 (2024): 234-245. https://doi.org/10.1038/nature12373.

❓ Common DOI Questions

Q: What if the article doesn't have a DOI?

A: Not all articles have DOIs, especially older publications or articles from smaller journals. If there's no DOI, use the URL instead. For print-only articles, omit the DOI/URL entirely.

Q: Should I include "DOI:" or "doi:" before the number?

A: It depends on the style:

  • APA: Use https://doi.org/10.xxxx (no "DOI:" label)
  • MLA: Use doi:10.xxxx (lowercase "doi:" prefix)
  • Chicago: Use https://doi.org/10.xxxx (no "DOI:" label)

Q: Can I use the DOI.org link to access the article?

A: Yes! Just type https://doi.org/ followed by the DOI number into your browser. Example: https://doi.org/10.1038/nature12373. This works even if you don't have access to the journal.

Q: Are DOIs case-sensitive?

A: No! DOIs are not case-sensitive. "10.1234/EXAMPLE" and "10.1234/example" point to the same article. However, it's best practice to copy the DOI exactly as it appears.

Q: Do DOIs expire or break?

A: No! That's the whole point of DOIs. Even if a publisher moves the article to a new website or the journal changes names, the DOI will always redirect to the correct article.

💡 Quick DOI Tips

  • Always use DOIs when available - they're more reliable than URLs
  • Copy DOIs carefully - even a small typo will break the link
  • Format as https://doi.org/10.xxxx - this is the modern standard
  • Test the DOI link - click it to make sure it works before submitting your paper
  • Don't add periods at the end - DOIs don't end with punctuation

✨ CiteForge Handles DOIs Automatically

When you paste a DOI into CiteForge, we automatically fetch the article details and format your citation perfectly. No more worrying about DOI formatting rules!

Try CiteForge Now →

Disclaimer: This guide provides general information about DOIs. Always follow your instructor's specific citation requirements and verify against official style manuals. Citations provided as-is.

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