What Is the Dunning-Kruger Effect?

(Last Updated On: October 17, 2019)

What Is the Dunning-Kruger Effect?

Have you ever walked into a room and thought you were the smartest person there? Perhaps you’ve met someone who behaved that way–and you probably didn’t really like them. Or maybe on the other end of the spectrum, you’ve thought you were either better or worse than the average person in a given group. Generally speaking, at some point in your life you’ve probably thought you were better than average at something. Maybe not to the point of being a conceited jerk about it–but enough to confidently think you can take on most of the competition. But if you are super conceited, you may want to think again. Because the Dunning-Kruger effect will slap you upside the head. So, what is the Dunning-Kruger Effect?

What Is the Dunning-Kruger Effect?

Illusory Superiority

It probably shouldn’t come as a surprise to you that the Dunning-Kruger effect was penned by people who shared that name. Chiefly, David Dunning and Justin Kruger. 

The long short of the story; they thought that incompetent people were less likely to recognize their own incompetence. Below you’ll see what David Dunning had to say about it.

“In short, those who are incompetent, for a lack of a better term, should have little insight into their own incompetence–an assertion that has come to be known as the Dunning-Kruger effect.”

We can’t be the only ones who see a lick of irony here, right? The gatekeep-y phrasing is a fun time, as well as the way Dunning refers to his own ideas (granted, research writing has some standards that can get a little funky, making one look a little self-indulgent). Regardless, it implies a level of high-self evaluation that could also illustrate the Dunning-Kruger effect in Dunning’s own writing. If he were incompetent in his research, he wouldn’t know. Anyway, that was fun.

But the idea does kind of hold. The origins of the Dunning-Kruger effect can be simplified to “why do people who can’t do things think they can in fact do that thing?” Let’s be real, we’ve all seen this at least in GIFs on Facebook. Someone who has never used a skateboard before trying to do some weird flip off of a roof and eating it. Or, one of the biggest prime examples in our opinion, drivers doing dumb things.


In all honesty, we kind of just wanted an excuse to use the word “metacognition.” The linguistically alert out there will recognize this as basically meaning “thinking about thinking.” Regardless, it’s important to discuss when we’re talking about an effect related to self evaluation. Namely, an effect related to the inability to self evaluate.

Not that being aware of the Dunning-Kruger effect makes you immediately immune to it. But it may make you less susceptible to it if you’re really giving it a good think. 

Dunning-Kruger: Origins

We’re going to namedrop the writings of both Dunning and Kruger, because once again, they sound very gatekeep-y. Before the Dunning-Kruger effect had become a widespread thing, the pair did a study in 1999, “Unskilled and Unaware of it: How Difficulties in Recognizing One’s Own Incompetence Lead to Inflated Self-Assessments.” There’s also “Why People Fail to Recognize Their Own Incompetence,” but we digress.

You may enjoy the first case of the study though. You might have heard of those two bank robbers on the news a really long time ago. The ones who scribbled with sharpies on their faces because they thought it would fool the facial recognition software?

Well, before those two brainy burglars came a man named McArthur Wheeler. He’s basically not known for much outside of his relation to the Dunning-Kruger effect; since his actions spurred the study into it. What Darwin-Award-esque action could lead psychologists into studying how stupid people are? 

Invisible ink, we’re glad you asked. Wheeler tried to rob a bank by being invisible to the security cameras. Which, in all fairness, is something we’d give a lot of thought when robbing a bank. Not that we at Sporcle rob banks. 

Here’s where Wheeler went wrong. He saw somewhere that lemon juice could be used as a form of invisible ink. So what else would a peak-intelligence upstanding burglar do but cover his face in lemon juice, thinking it would hide him from the security cameras later?

Yeah it didn’t work.

Dunning-Kruger Effect

Studies and Dunning-Kruger

So it was that after seeing such a lemon-headed outcome, professor David Dunning and his trusty graduate student Justin Kruger would begin their research. 

At first, they took a bunch of poor undergraduate psychology students. Not that they were exploited, undergrads are just generally poor.

Anyway, the pair would quiz their sample on a handful of things. Grammar, logic, and even how funny jokes were (they brought in real comedians for this). The students all had their scores compared (as well as being polled on their own self-assessment), and thus the Dunning-Kruger effect manifested itself.

As this post would suggest, the lowest scoring students self-assessed higher than they scored. However, the degree by which this occurred was staggering–those who scored the lowest thought they were better than 66% of respondents. If they were in a race of 10 people, that’s like last place being convinced they were 3rd place. 

But wait, there’s more. As expected, people who did better generally saw their self assessments line up more with their true scores. However, those who did the best had a tendency to think they did worse than their scores would suggest.

So it was posited that the Dunning-Kruger effect takes place as a result of ignorance. The only way you can test well in your math class is by knowing math on some level. If you know no math at all, you won’t even know what you’re doing wrong, since you don’t even know what to do right. You’re ignorant to your own ignorance.

They also found that people who were trained over time in logic puzzles also gradually became better at assessing themselves by proxy. This supports the previous position that the Dunning-Kruger effect is a result of people not knowing how good people generally are at something.

So What Can You Do?

Well, the first thing to do is really to just have some humility. Knowing that you’re predisposed to think you’re better than the average is the first step. You might not be the worst ever, you’re probably pretty good–but you rarely will be the best ever. 

Basically, we’re not saying you suck at everything, but we are saying we could all do with some more humility.

Want more dumb people in your life? Here’s a quiz on Dumb and Dumber.



About Kyler 706 Articles
Kyler is a content writer at Sporcle living in Seattle, and is currently studying at the University of Washington School of Law. He's been writing for Sporcle since 2019; sometimes the blog is an excellent platform to answer random personal questions he has about the world. Most of his free time is spent drinking black coffee like water.