Common Knowledge 101: What You Need to Know to Pass

In most academic circles, common knowledge does not need to be cited in a research paper. This can be a great time-saver since it’s one less APA, MLA format, or Chicago style citation you need to create. But first, you need know the answer to this big question: What is common knowledge? Since plagiarism is considered a serious offense both inside and outside of school, being sure about what common knowledge is can save you from a lot of unnecessary trouble and stress.

What is common knowledge

In general, common knowledge is something known or understood, by reasonably educated people without the need to confirm it through research. Common knowledge is a fact that cannot be argued. It’s usually something you know off the top of your head.

Common Knowledge Examples:

  • We live on the earth.
  • Paris is the capital of France.
  • There are 365 days in a year.
  • In grammar, a “book” is a noun.
  • Bananas are yellow when ripe.

Not so common, common knowledge

At first common knowledge is a straightforward concept, but it’s a little more challenging when you start to realize that what is considered common knowledge changes based on who we are talking to. Here are a few factors that can have an effect on what is considered common knowledge.

Nationality

In the United States, it’s common knowledge that the national bird is the bald eagle. If you were talking to a group of Australians about the fact above, it probably wouldn’t be considered common knowledge.

Academic field

When addressing a group of veterinarians, the fact that a cow has four stomachs is common knowledge. That same information presented to accountants is not common knowledge.

Cultural group

We can reasonably assume that a member of the Islamic faith would know the five pillars of Islam, but when writing a college paper for an Introduction to World Religions class, this information is best cited. Keep in mind, if the five pillars are presented to a group of religious Ph.D. candidates, a citation is not needed because these are well-known facts in this academic field.

As you can see, what is common knowledge in one group is not common in another. To help you protect yourself from plagiarism, we have designed a little test.

The common knowledge test

To figure out, if the information you are presenting is common knowledge. Visualize the audience you are writing for and ask yourself these questions:

  • Do ninety percent of these people know this information already?
  • Is there any reason for a member of my audience to question the validity or source of my information?

If the answer to question number one is “yes,” and question two is “no,” you do not need to include a citation.

What if I’m not sure about the answers to those questions?

If you are not sure, take the safe route and cite the information. You will not be faulted for taking the precaution. Proper citing can be time-consuming. Because of this, it is very tempting to label everything common knowledge. What feels like a nice shortcut in the middle of a big paper could lead you to a huge hassle down the line.

Now that you know how to identify common knowledge like a pro, you can use proper citation when you need to and feel confident leaving it out when you don’t.


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