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Every time visitors land on your ecommerce page, there are challenges, fears, and doubts that prevent them from confidently buying. Remove this friction by turning great customers into your best advocates using social proof. A/B testing social proof is a necessity in your optimization journey to finding the best ways to earn trust from users.

What does social proof mean?

Tucker Schreiber: “It’s a psychological phenomenon where we look to the opinions of others and additional “signals” to help us make decisions. It’s also a powerful persuasion tool you can use in your business to influence potential customers who are trying to make a buying decision.”

It could be anything from a review to a customer-submitted photo of a product.

More than 70% of consumers say that they look at product reviews before a purchase and that they trust them 12x more than the manufacturer description. By showing the behavior of happy buyers before them, you are leveraging this fact by engaging them with trustworthy content that leads to a sale.

Reviews Social proof

Other interesting insights:

  • Reevoo reports that products with 50+ reviews can mean a 4.6% increase in conversions
  • They also found that reviews produce an average 18% uplift in sales
  • Bazaarvoice has found that visitors who interact with reviews & customer questions are 105% more likely to purchase and spend 11% more than shoppers who don’t

So if social proof has such a major effect on shopper experience, how does a company find ways to best apply it to their site?

A/B Testing.

There’s much more than product reviews when it comes to social proof. Testimonials, comments, customer questions, ratings, comments, endorsements, and number of purchases are just a few. If it increases the trust of shoppers by highlighting the behavior of previous customers, it’s social proof. But with so many types and ways to present this type of user-generated content, you must test how to best use it for your audience.

Angie Schottmuller: “Social proof is credible when authentic specifics and signatures add value enough to build trust.”

So whether you’re new to testing or need to consistently get tests out the door, social proof deserves some optimization attention. We already know that winning experiments are hard to come by in ecommerce. Up your chances by identifying ways to make social proof resonate with your particular visitors.

Here are ways to use social proof to earn the trust of visitors and turn them into shoppers:

Improve Reviews by Getting & Providing Context

Most ecommerce businesses list reviews on their product pages for potential buyers to read positive customer experiences. But not every review is relevant to a user because he or she may not be the same persona as that writer. To improve the experience, ask customers who write reviews to provide context. This includes information about themselves such as gender, age, location, reason for interest in the product, and more. This way, new buyers identify with review writers and trust their opinion even more.

See how Eastbay builds this relationship on a product page for an athletic shoe:

Eastbay Social Proof


As you see, there is an overall rating system for all reviews. For individual reviews, customers are asked to answer who they bought the product for, when they purchased it, their athletic skill level, and how the product is being used. A user reading this information has a better picture of how they’d use the product themselves.

Filtered Social Proof

To maximize the effect of reviews, Eastbay also provides a filter with many options. Businesses do not always implement this feature, but customers find it useful to find the most relevant reviews. Simply providing reviews is just the first step in improving your site; continue to optimize this feature and give your customers what they need in order to convert.

  • Ask your customers contextual questions when they leave a review
  • When displaying reviews, provide the context at the beginning
  • Provide an option to filter reviews for users
  • Test new features, questions, or elements for reviews with the goal of building more trust

Use “Trending” Sections To Show What Shoppers Buy

The behavior of previous users has a powerful persuasive effect on new visitors. Show products or pages that are trending during a user’s experience and they will be inclined to explore. Using the behavioral data to emphasize trends will highlight opportunities for promotion that you would have otherwise missed.

Let’s look at this example from Dick’s Sporting Goods:

Trending Social Proof

Their customers determined these product types to be momentarily popular, which means that these pages are more relevant. A user may see the shoe sale and think “Everyone is taking advantage of this — maybe I need to, too”.

Etsy also uses this tactic:

Etsy Social Proof

The site features crafted products from vendors who are users of the platform, so a constant stream of new items are added every moment. This makes it difficult to for buyers to find the perfect item. But showing trending items eases the friction for users that are casually shopping or browsing by subtly driving them towards decision making.

  • Show trending items at the beginning of the user’s flow
  • Try grouping trending items together for seasonal specials
  • Test presentation of trending items or combining elements, such as reviews and ratings

Show the Number of Conversions

Similar to trends, displaying the number of people who have converted or purchased is also very persuasive. Display this number close to your CTA as the final push for your users. Each increase in that conversion number is a vote of confidence for your user.

LivingSocial also does the same thing for their products by showing the number of purchases:

Number of Conversions

An item’s popularity drives new customers to purchase the item. Users feel validated in their interest because so many others have bought it. They also feel a sense of urgency that the item could be sold out soon.

  • Display number of conversions next to your CTA
  • It is not always purchases; it can be number of subscribers, clients, demo requests, social shares, downloads, etc.

Show Items That Customers with Similar Tastes Liked

If users on a product page are uncertain about the item, recommend other products based on the tastes of customers just like them. This type of cross-selling encourages visitors to find a more ideal item or an additional item for their purchase. This approach uses the opinion of other users to feature specific products.

On product pages, Express shows items that “shoppers like you also love”:


Similar Customers

Target uses a similar tactic, but shows what customers actually purchased instead:

Target Social Proof

  • Track how customers interacted with your site before conversion
  • Use that data to provide product recommendations that new buyers trust
  • Test whether your audience prefers to see items that previous customers viewed or purchased

Leverage User-Generated Content

If you have happy, vocal customers, empower them to share their enthusiasm for your site or store. Nothing establishes trust and engagement as well as user-generated content. After all, your users determine the success of your business so they know what resonates with other new customers. So if your audience has positive sentiment about you elsewhere, make sure to aggregate and leverage it on your own site to increase conversions. For example, a feed of tweets surrounding your brand located on the sidebar or a collection of blog posts written about your services. Showing off something like this gets potential customers engaged in the total experience of your brand, which increases their lifetime value.

ModCloth is a popular example of this because they present user-generated content in an fun, interactive way:

modcloth social proof

Because they’re a fashion store, they encourage previous buyers to upload photos of themselves in their favorite outfits in the style gallery. These outfits are then featured based on a voting system by other users. This serves as a “visual” testimonial to new users on the site.

modcloth customer photos


Modcloth continues to leverage the content by linking to the products worn in the photos, creating an experience that combines engaging content, social proof, and product page components.

  • Find or create a source for user-generated content
    • Look on social networks where your audience lives and locate or start a conversation about your brand
    • Establish an area on your own site to collect and gather user-generated content
  • Encourage interaction with the content through tactics like voting systems or rewards
  • Connect the content to business goals with tactics like product links or form submissions

Categorize Customer Testimonials According to Needs

When it comes to testimonials, they’re a bit different than the types of social proof we’ve talked about so far. They’re more personal and usually speak to the brand or store as a whole, rather than a specific product. Users value this because where a product comes from is just as important as the product itself. With testimonials, you earn a type of trust that resonates longer, which often turns into lifetime value.

Marie Forleo’s B-School, which sells online business training courses, uses social proof very well throughout its site, especially its testimonials. Just look at its front page:

Social Proof Category

The header features a user-guided carousel of links to video testimonials. The UX allows visitors to click a type of motivation that matches it with an appropriate testimonial:

Social Proof Categories

The site really cements this idea when you go to their actual customer stories page to see a full list of testimonials.

Social Proof Category Nav

Each testimonial shows an image (usually linked to a video) with the customer’s name, title and organization, and a nice quote. But notice how the left rail provides navigation that actually categorizes these testimonials based on goals of a visitor.

Social Proof Category

When one moves down and clicks “Win as a parent & entrepreneur”, the page scrolls to a happy customer who speaks about that whether in the quote or in the video.

So to start testing a similar idea for your own site:

  • Identify what your visitors really need in order to trust you
  • Identify what your visitors’ goals are
  • Create categories around those and begin collecting testimonials that connect
  • Present these testimonials in a clear, easy-to-navigate UX
  • Test different versions of that UX as well as the number of categories
  • For bonus points, test varying content formats such as video, too

Test Social Proof Throughout the Purchase Experience

It’s not just about testing different types of social proof, but also where it covers your site. A shopper will go through multiple pages before checking out and each point is an potential opportunity for a testimonial, review, or customer-generated content. Find out how where your audience needs social proof the most throughout your store.

For example, product reviews for Home Depot start appearing on the product category page in the form of a cumulative star rating:

ratings on category

After clicking into one of the grill products, you are given the basic manufacturer’s description along with specifications, but when you scroll down to read these elements, the star rating actually appears and becomes part of the top navigation:

rating in top nav


Continuing down the product details page, we then come across a customer Q&A section. These questions are both posed and answered by customers, making it a valuable and trusted resource:

customer questions

Near the end of the product details page, we finally come across the detailed section of customer reviews where specific entries can be read. Along with that, customer images are provided in a gallery along with a recommendation rating. At this point, a shopper has more than enough unbiased information and is excited to purchase.

home depot customer reviews

  • Identify parts of your site where customers are making decisions about products (typically, this is the category and details page, but it’s interesting to consider shopping cart and checkout form, too)
  • Even on one page, test the degree of emphasis (the amount of the page that social proof uses and how users continue to see it)
  • Don’t forget that each area of your site might mean a different type of social proof is needed. Perhaps social media mentions resonate better early in the flow, but specific reviews are needed towards the end.

Conclusion: Keep Testing Social Proof As Your Audience Evolves

Adding social proof is an effective method to optimize the buying experience when used properly. Don’t simply list reviews; find engaging ways to present content or data from happy customers. Not only does this remove friction, but it turns user-generated content into advocacy that encourages new visitors to buy. Just remember, audiences change over time in the way they interact with your content; just because one type of testimonial boosted conversions a year ago, doesn’t mean that element or area shouldn’t constantly be tested again. Continuously find ways to optimize how social proof earns trust which, in turn, generates sales for your store.

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