19 cognitive biases applied to marketing and conversion optimization: anchoring, scarcity, social proof, loss aversion and more ethical CRO techniques.
Cognitive biases are psychological effects that produce a deviation in mental processing, leading to distortion, inaccurate judgment, illogical interpretation, or what is generally called irrationality. They arise from the interpretation of available information, even when the data is not logical or unrelated. The existence of cognitive biases emerges as an evolutionary necessity — our brain’s way of making quick judgments in the face of stimuli or situations where it cannot process all available information.
Source: Wikipedia
People make decisions based on their emotions. Psychological triggers are a key factor in that decision-making process. The most successful brands manage to connect with our emotions time and time again.
Before diving into this list of 19 cognitive biases to optimize your conversion rate, it is important to highlight a simple ethical principle that should guide your marketing strategy:
Would you do it to your mother?
Misleading promises, manipulation, spam, dark patterns… avoid bullshit marketing. Marketing can be a genuinely valuable activity that creates real worth in our society.
Don’t be a jerk — think about your audience before using certain techniques.
An initial value — the “anchor” — serves as a mental reference point or starting point for estimating an unknown value. When an anchor is presented first, it exerts a magnetic pull, drawing estimates toward itself. Anchoring works even when the initial anchor does not represent a reasonable number.
By adding a high-priced item to your product list, everything near it looks like a bargain. When we estimate a numerical value, we tend to be susceptible to the power of suggestion. Any related value we hear just before making our estimate has a statistically significant impact on the number we will estimate — even when we are warned in advance about the persuasive power of anchoring.
Usage:
Example: On donation sites like UNICEF, presenting a suggested amount first anchors the visitor’s perception of what a “reasonable” donation looks like.
Do you think humor is not part of cognitive biases?
As a reminder, a cognitive bias is anything that leads a consumer to make an irrational decision.
For example, buying a product simply because the ad made you laugh. You know nothing about the product’s qualities, but you enjoyed the ad.
Why does it work? Because nothing is more powerful than humor.
Whether it’s to make your mark or to build a community, it’s an ultra-efficient way to sell more.
Example: Hut Weber, a German hat company known for its bold and irreverent advertising, perfectly illustrates how humor can make a brand memorable.
The availability heuristic occurs when someone relies on information that is immediately available or comes to mind quickly during a given event. As a result, we may judge these events as more frequent or reliable than others.
For example, after seeing an article about people winning the lottery, you might start overestimating your own probability of winning.
We tend to heavily orient our judgments toward more recent information, causing new opinions to be skewed toward the latest news.
Usage:
Example: Dollar Shave Club’s “Get ready to look, feel, and smell your best” positions key benefits immediately before the purchase decision point.
This is the tendency to think or want something because our reference group thinks or wants it. In other words, we do what our friends do.
Everyone is susceptible to the effects of trends. Don’t believe it? Look at the queue outside an Apple Store on the day of a new iPhone launch…
Usage:
When customers are offered only one option, they tend to look for alternatives, postponing their purchase.
We are reluctant to choose an option, even if we like it, when we have no other choice. If only one option or product is presented, we consider our choice in terms of “take it or leave it” rather than “compare options.” This implies that a product is purchased more often when presented alongside several competing models.
Usage:
We are social animals. We need to feel recognized, identified, members of a group. From rock bands to influencers, from political parties to sports teams — everyone knows that the belonging bias is extremely powerful.
Usage:
Example: Premium loyalty programs like Emirates Skywards or airline elite tiers play perfectly on this bias.
This is a well-known cognitive bias that affects all of us — yes, every single one of us.
The vast majority of our purchases are the result of our emotions. Very few purchases are the fruit of a rational exercise. But sometimes we need to feel good by rationalizing our purchase after the fact…
I needed that €1,000 phone. It has incredible features that genuinely improve my life.
Post-purchase rationalization is also known as “buyer’s Stockholm syndrome.” Once customers have made the buying decision, they are “captive” — even if they don’t like the product after they start using it, they convince themselves they like it.
Usage:
Confirmation bias is the very common tendency to seek out and consider only information that confirms our beliefs, while ignoring or discrediting information that contradicts them.
This is the bias that we, as conversion optimization (CRO) professionals, must control at all times. It feels great to be right — and if we can find data that supports our argument, it becomes very easy to ignore data that says the opposite.
In marketing, the decoy effect (also known as the asymmetric dominance effect) is the phenomenon by which consumers will have a specific change in preference between two options when a third option — which is asymmetrically dominated — is also presented.
Usage:
Example: On SaaS subscription pages, the middle-tier plan often acts as the decoy, making the premium plan appear much better value.
The loss aversion bias describes the tendency to assign greater value to an object one already possesses than to the same object one does not yet possess. For example, a homeowner might estimate the value of their home as higher than what they would be willing to pay for an equivalent property.
Usage:
Example: Booking.com is the master of this technique: “Only 2 rooms left at this price” — “15 people are looking at this right now.”
This technique involves gaining a small commitment before asking for a larger one. For example, before asking someone to buy your software, you give them a limited free trial (limited by time or features).
Usage:
Example: Trello’s “Start for free — free forever” offer is a textbook foot-in-the-door application.
The “Identifiable Victim Effect” refers to the tendency of individuals to offer greater help when observing a specific, identifiable person (“victim”) in difficult circumstances, compared to a large, vaguely defined group with the same need. […] Concrete images and representations are often more powerful sources of persuasion than abstract statistics. […] The effect is summarized in the phrase (commonly attributed to Joseph Stalin): “One death is a tragedy; a million deaths is a statistic.”
Source: Wikipedia
Example: UNICEF campaigns that feature a single child — with a name and a story — consistently outperform campaigns featuring statistics about millions of affected children.
Until recently, the term “Ikea Effect” made me think of the frustration of spending 40 minutes looking for the exit in an Ikea store.
But that’s not it. The Ikea Effect is actually very simple: we give disproportionate value to things we have created ourselves (even only partially).
Usage:
Whenever possible, offer your customers the ability to customize your products and services to meet their needs (or whims). If customers feel that part of what they purchased came from their own creativity and effort, they will be willing to pay more for it.
Example: Nike By You (custom sneakers), Monoprix personalized gift boxes — any product that lets users add their own touch leverages this effect.
The more we are exposed to something or a message, the more we tend to trust it. This is precisely why multinationals spend millions of dollars on advertising — their goal: make their product part of our mental landscape so that we reach for it “automatically” at the supermarket.
Usage:
The scarcity effect is a cognitive bias that leads individuals to place a higher value on a rare product than an abundant one.
Gold and other precious metals have high value because of their scarcity. Diamonds are worth more than gold for the same reason.
Usage:
Example: Booking.com — the king of “scarcity” messaging in everyday commerce.
One of those cognitive biases that reminds me of the phrase: “Things were better before.”
When something new comes along, it inevitably brings advantages and disadvantages. This is when status quo bias appears — essentially a defense mechanism against an unstable situation, by avoiding change.
Sometimes this mechanism genuinely protects us. At other times, we overestimate the risks and even create them, preventing us from making a fully considered decision.
For example, an iPhone user will tend to see switching to an Android phone as too difficult — even though these smartphones are no longer that different today.
Usage:
This refers to our tendency to prefer a smaller reward that comes quickly over a larger reward that takes longer to arrive. It is our brain’s automatic preference for immediate gratification — a system that has helped us survive for millions of years.
Usage:
Example: Hotjar’s free plan lets you start recording visitor sessions immediately — no credit card required.
Social proof, a term coined by Robert Cialdini in his 1984 book Influence, is also known as informational social influence. It describes a psychological and social phenomenon in which people copy the actions of others in an attempt to undertake appropriate behavior in a given situation.
Usage:
Example: Nike + Colin Kaepernick is a perfect case study: controversial but massively effective at consolidating a core audience.
Our decision-making processes are not as rational as we would like — and we are heavily influenced by the way information is presented (positive vs. negative frames).
The framing effect is a cognitive bias by which a person’s preferences for a decision problem depend on how it is presented — its “frame.” The same information presented differently can lead to completely different choices.
Usage:
Example: L’Oréal doesn’t tell you that aging is the beginning of the end — they tell you: “Because you’re worth it.”
We apply cognitive biases to improve results in both PPC campaigns and our CRO projects.
Which cognitive biases do you find most effective in your field?
30 minutes to review your situation and tell you exactly what I would change. No pitch, no sales proposal.