How Anchoring Influences UX
Cognitive Biases, Anchoring Effect, Behavioral Economics, UX Psychology, Decision Making, Pricing Strategy
Would you pay your age – in dollars – for a bottle of wine? Probably not. But here’s the strange part: that completely irrelevant number would still influence what you’d guess the wine is worth.
That’s anchoring. It’s a mental shortcut where the first piece of information we see – relevant or not – becomes the reference point for every judgment that follows.
In this article, I’ll show you real experiments (including Dan Ariely’s Social Security Number study) and two practical ways to use anchoring in your UX design: setting good defaults and showing original prices.
How Anchoring Influences UX: The Power of First Numbers
I’d like to try a quick experiment. Grab a pen and paper. Write down your current age. Would you pay that much, in dollars, for this bottle of wine? If not, how much do you think this wine is worth – without doing any research? Write that number down too.
Obviously, your age is a completely irrelevant number to how much this bottle of wine is worth. You might be anywhere between 18 and 100 years old. But I’ll bet none of you guessed that the price of this wine is $1,000 on a good day. Any of your ages would have been a bargain.
The Social Security Number Experiment
Dan Ariely and his colleagues did a similar experiment. Instead of ages, they used the last two digits of people’s Social Security Numbers. They showed different items (Bluetooth keyboards, bottles of wine, other products) and asked participants: would you pay that number – those two digits – in dollars for this item?
Here’s what happened for a Bluetooth keyboard. The bids for the exact same keyboard ranged across a $40 span. All influenced by that initial, completely arbitrary number.
This is anchoring.
What Is Anchoring?
Anchoring is a judgmental heuristic that involves using some initial piece of information to make a judgment – whether that information is relevant or not. That initial piece “anchors” the person, so all judgments lean heavily on it.
This isn’t just a numbers‑based phenomenon. Anchoring can relate to how much we rely on initial data to make any decision.
Two Ways to Use Anchoring in UX Design
1. Offer a Good Default Value
Bad example:
“Your total is $25.99. Would you like to donate money to save the animals?”
“Ehh… No thanks.”
What went wrong? No good default!
Better example:
“Your total is $25.95. Would you like to round up by 5 cents to save the animals?”
“Sure, why not.”
Setting a good default removes uncertainty and establishes expectations. The donation went from high‑stakes to low‑stakes.
2. Show the Original Price
Just saying an item costs $100 gives the buyer an anchor of… $100. But if you tell the buyer the **original price was $500**, this anchors them with a much higher perceived value – making $100 feel like a bargain.
Why This Matters for UX
Anchoring is one of many shortcuts we take as humans. While it could lead to incorrect estimates, the more mindful we are about it, the better our design choices will be.
Use anchoring ethically to help users make decisions – not to trick them.
Download our ‘Cognitive Biases in UX’ Cheat Sheet – 10 mental shortcuts (including anchoring) with examples and design fixes.
