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Tips & Tricks for Building Your Experimentation Program words to persuade. Carefully write (and present) copy that resonates with visitors to create an improved user experience and increase conversions. Simply editing language to appeal to your customers often results in significant gains. But first, understand how your customers can be persuaded with words.

These tips apply a conversion-driven approach to your copywriting:

Consistently Apply (or Omit) The Oxford Comma

There are two types of copywriters: those who use the oxford comma, and those who don’t. Its use has been controversial in language and comes up often when writing web copy. According to a poll by FiveThirtyEight, those who believe they have excellent grammar prefer the oxford comma:

Oxford Comma Data

Younger people tend to prefer it, too:

Oxford Comma Age

So the use of it depends on your audience and their preference can always be learned through testing. But whether you choose to use the oxford comma or not, your choice should be consistent throughout the user’s experience. This way, you’ll avoid confusion, especially in important lists, such as benefits in your value props or features of your product.

Write & Present Short, Scannable Copy

When writing copy for your page, remember that users are there to quickly gather information. Every word on your page needs to be necessary and communicate value. So when a visitor enters your site, they can scan your copy and understand why your company or product is beneficial. This drives users to convert or move to the next buying phase. Make important words stand out, avoid long blocks of text, and use succinct phrases. See how Evernote does it on their home page:

Each text portion of the Evernote page takes a quick moment to read. All text blocks are spread apart and very direct in language.

Each text portion of the Evernote page takes a quick moment to read. All text blocks are spread apart and very direct in language.

Here are ways to improve the scannability of your copy:

  • Shorten most copy into phrases
  • Bold important facts, benefits, & phrases
  • Break up long blocks of copy
  • Use bullets and numbers, where applicable
  • Make font and color easy to read; don’t let photo background distract away from copy
  • Remove unnecessary info; every word should be needed

Replace Empty Questions with Immediate Value

Many people use empty questions in headlines as a setup to list benefits in body copy, but this is a waste of words. Instead, tell your users up front about value and how they should act upon it. Drive them to convert with words like “Get this…now!” or “Receive your free….immediately!”. Being imperative and urgent drives them to convert. Britannica Online found out the effects of this by A/B testing a variation that emphasized the value of a free trial instead of the original empty question:

Original version that uses an empty question as its headline.

Original version that uses an empty question as its headline.

Variation that emphasizes the value of a free trial with direct, active headline copy.

Variation that emphasizes the value of a free trial with direct, active headline copy.

The copy change resulted in a 103% lift for signups.

  • Identify the primary goal of your page and the value it gives users
  • Find and replace any empty questions on pages by directly emphasizing user action and value
  • Use active voice and imperative language, like “Act now to receive a free trial!”

Focus on Benefits in Value Props (Not Features)

The value proposition is an important part of your page copy. It tells users why they should be using your product or service. But be careful; many companies emphasize features or characteristics here. Instead, you want to immediately grab users’ attention and convey the actual benefits or results they should expect. Take a look a SumoMe’s value prop copy for each of its products:

SumoMe Value Props


  • Use actual data in your copy to back product benefits (ex. SumoMe’s List Builder says it increases signups by 20%)
  • Speak directly to customers (use second person perspective) and tell them how it improves their current status

Use Listed Value in Popups

Your page may use a popup feature to collect signups from users, which often yields successful results. Ensure you’re maximizing its effectiveness by avoiding generic copy and actually appealing to your visitors. Let them know that they will be rewarded in exchange for submitting their email info. Do this by adding bullet points or checkmarks that specify the value they can expect in their inbox. ContentVerve tests this out:

ContentVerve Pop-Up

The result was an 83% increase in signups when the popup included specific copy about updates.

  • Don’t use generic copy in your popups; be specific about the rewards of submission
  • Test different rewards (ex. exclusive articles, eBooks, worksheets, etc.)
  • Use short phrases in a list format, such as bullet points or checkmarks, for quick reading

Test CTA Button Language on Customers

Your CTA language is major factor in converting visitors or moving them down the funnel. Even a small change to the few words on a button can alter your conversion rate significantly. A/B testing this will give you insight into how your customers react to particular language. For example, it could be assumed that “Buy Now” would outperform “Add to Cart”. But Analytics Inspector, discovered that this is not always the case:

CTA Language Test

They found out that “Buy Now” actually decreased their conversion rate by almost 10%. They also tested “Purchase Now” as CTA button copy, which performed even worse. The customers of this client reacted negatively to the new variations because it conveyed too much commitment, while “Add to Cart” gained more clicks because it was less aggressive.

Billund Airport, an airport in West Denmark, tested their CTA using VWO. The original used “Shop Online” and the variation used “Buy Tax-Free”:

Billund Airport CTA Language


The test found that the variation won by almost 50%. The airport learned that their audience perceived the new copy to be more valuable; it was more specific and used the word “free”. Remember, continuously tweak and test your CTA copy to find out what really drives your customers.


Use these methods to enhance your copy and improve your communication of value to visitors. If they’re able to easily interpret benefits, the more likely they’ll convert. Continuously tweak and edit your words to find out the type of language and presentation that resonates with your customers.

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