The Cognitive Bias Codex by search volume

Some of you might know that the whole reason we started this project was Radu's interest in the Cognitive Bias Codex.

We love the Cognitive Bias Codex and we believe it did an incredible job at making the general public aware of cognitive biases. We have since learned more about it and we learned that it is not perfect. Some experts told us that the categories are not as well defined as they could be; others said that some concepts listed aren't even cognitive biases. To be quite honest, we don't feel that we're the right people to fix it (if indeed it needs fixing) so that's not what this post is about.

As we were gathering definitions for the Cognitive Bias category of BrainyTab, we came across some that we never heard about. It got us thinking about how some biases are a lot more popular than others and about a way to visualise the popularity of each bias. Because we don't have access to all the academic documentation required to measure citations and popularity, we decided to look at the number of Google search results for each bias. We'll explain the rough methodology we used at the bottom of this article; spoiler: it's not perfect.

Initially, we wanted to have all the biases included in one chart because we thought that would be a nice way to visualise the data. That proved to be a bad idea because we ended up with a massive blob of dots that were impossible to interpret.
So we split it into 5 separate charts: the first one shows the main categories (e.g. Need to Act Fast, Not Enough Meaning, etc). The following 4 charts show each of the groups separately.
We also wanted to build the chart at scale and we hoped that we'll get somewhere where a bias with 100 search results will be 100x larger than a bias with 1 search result. Sadly that didn't work perfectly because of how the chart builder works but let us know on Twitter if you'd like to see that and we'll spend some more time thinking about how we can achieve that. Maybe we'll create a poster where 1 pixel equals 1 search result; if we do build that, we'll make it available to download.

How to use the charts:

  • The size of each dot is determined by the number of search results (i.e. the more search results, the larger the dot)
  • As you hover over each element, you will see the complete name of the bias or the category, and the number of search results.
  • Click on the categories to group and ungroup all the biases.

Cognitive Bias categories

What should we remember?

Too much information

Not enough meaning

Need to act fast

How we built this.


We got each number of search results by googling each bias. In most cases we looked for we only looked at the exact match results (e.g. we searched for "cognitive dissonance" meaning that Google showed us the number of results where the word "cognitive" was followed by the word "dissonance"). For others, we had to include the word bias in the search query (e.g. searching for Reactance alone gave us way too many irrelevant results so we looked at the search results for "Reactance bias").

We hope you enjoy this. Let us know what you think about it on Twitter or LinkedIn.