How to Use Psychology to Double Your Conversion Rate

tl;dr: apply influence principles to drastically improve your conversions. Use apps to help with this like Yotpo for reviews, Notify for social proof, and SumoMe for giveaways.

Conversion optimization is both an art and a science. An art, in that much of what you’ll test (copy, benefits, special offers) is specific to your product and target customer.

But, it’s also a science. To improve conversion rates, what you’re really doing is convincing a larger percentage of people to buy your product.

And to convince more people to buy your product, you need to do a better job persuading them that your app/product/service can help improve their lives. Fortunately, Robert Cialdini (bestselling author of Influence) has broken down the 6 elements that go into influencing someone.

I’m going to take these elements and show you how you can use each of them to boost your conversion rate. Let’s get started.

Social Proof — Influence Principle #1

That’s the idea behind social proof. Humans are social creatures — if we see that other people have purchase (and liked) a product, we’re more likely to make a purchase ourselves.

If you don’t already, try incorporating the following social proof elements into your homepage or product page to see how it impacts conversions:

  • Testimonials from the customers you want to reach
  • Reviews (the more the better)
  • Social media proof (showing Facebook likes, Twitter followers, etc.)

One of the best tools I’ve seen to add an element of social proof to your site is an app called Notify [1]. It basically pulls in recent sales from your store and displays them as pretty notifications on your storefront (example in lower left corner).

Adding elements of social proof like this (people are buying stuff!) can boost conversions as much as 40–80%.

So if you don’t have testimonials, many reviews or other social proof elements, get on it!

Reciprocity — Influence Principle #2

A classic example is the ‘free ebook’ many sites give away in exchange for an email address. They’re offering you something for free, which makes many people feel compelled to take them up on their offer.

You can test this principle of reciprocity on your store in a few ways:

  • Give away a free ebook or coupon to your site visitors
  • Reward people with a gift or giveaway after they sign up for your email list or finish a blog post you write
  • Set up a rewards program where your existing customers get $10 if they refer a friend to your site

In summary: people love free sh*t.

Commitment and Consistency — Influence Principle #3

If people commit, orally or in writing, to an idea or goal, they are more likely to honor that commitment.

This is often called the “foot in the door” technique. This principle is also why popups like this work:

As soon as you say “Yes,” you’re making a (small) commitment to “do this.”

Once you make the commitment to turn bounce traffic into revenue, you’re more likely to sign up for Bounce Exchange (the site the above popup is on).

How you can test this on your site to improve conversions:

  • Add a popup similar to Bounce Exchange’s (see above)
  • Have customers publicly support or commit to buying or using your product. If their friends know they’re fans of your product, they’re more likely to keep using (and buying) what you have to offer
  • Have customers post images of themselves using your product on social media

Each of the above are small ways to get your customers or visitors to “commit” to your product, which will make them slightly more likely to buy.

This brings us to Principle #4…

Authority — Influence Principle #4

That’s why you’ll see something like this on many websites:

For my own company, Kettle & Fire bone broth [2], we apply this principle on our homepage by including testimonials (social proof!) from a well-known author and a doctor.

How you can apply this principle:

  • Add testimonials from famous customers or influencers
  • Slap the logos of media sites that’ve covered you on your site
  • Include quotes from researchers, doctors and other authority figures about your product (or industry, if you don’t have actual quotes)

Time for our next principle!

Liking — Influence Principle #5

The more likeable, personable and friendly your site is, the more likely people are to buy from you.


That’s why people buy from brands like Dollar Shave Club, Chubbies and others that have a personality that customers can connect with.

This is the toughest principle to apply to improve your conversion rates. However, by injecting personality into your website copy, you’ll attract a certain type of customer that responds to your site’s personality.

This brings us to the last principle…

Scarcity — Influence Principle #6

Of course you have. You’ve been on the internet before.

This is the principle of Scarcity in action. This is why things like clearance sales, one-time offers and “only 5 left in stock!” drive purchases.

To apply this principle on your site, you can:

  • Leverage “limited time only” sales, where someone has a countdown timer with an expiring offer
  • Have a 24 hour real-time clock showcasing a discount or sale
  • Show people how many units of a product are left in stock. This app is a useful way to do that

And that’s it! Those are the 6 influence principles laid out in a way that you can apply them to improving Shopify conversion rates.

The best way to improve your conversion rates is to do multiple A/B tests where you apply the above principles. I’d recommend testing different:

  • Headlines
  • Offers
  • Copy
  • Images
  • Testimonials
  • Reviews
  • Button sizes, colors, copy
  • Website layout

By running 1–2 A/B tests per week, in just a few months you should be able to improve your conversion rate by 20–200%!

There are huge conversion gains to be gotten by applying the above principles. Go forth and apply them.



Founder at bone broth.

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