Understanding Incremental Lift

The formula for incremental lift is (test value – control value) / control value. The results is a positive or negative percent. Incremental lift provides the percentage of conversions that were received as a direct result of product page optimization. You can use it for values such as revenue, add-to-cart rate, visitors, or other key metrics. At SellPoints we are laser-focused on lift in add-to-cart rate, for two reasons. It is a critical point in the consumer’s buying decision, and it is the point where our interactive content makes the most direct difference.

Let’s illustrate incrementality by calculating incremental lift in add-to-cart. This lets you compare two groups of consumers. For example, the consumers are given the SellPoints interactive experience vs. a control group of shoppers who were not.

The formula for calculating incremental lift is (new value - base value) / base value. You can use it to calculate the change in add-to-cart rate, revenue, product detail page, or other key results.

Remember when you use the incremental lift formula in your spreadsheets and calculators, the subtraction happens before the division. So those parentheses matter in the equation: (test value – control value) / control value.

Why Incremental Lift is important

Why then is incremental lift useful? If we told you three months after enhancing your product page with SellPoints that you had a 15% conversion rate, it might sound pretty good. But wouldn’t you want to know what your lift would be without SellPoints over the same time period? SellPoints Incremental lift shows the amount of change between the test and control over time, accounting for seasonal trends, spikes in traffic due to retailer promotions and other outside marketing initiatives. Put simply, SellPoints incremental lift tells brands how many more sales they got with SellPoints solutions versus how many they would get without.

Why Focus on Add to Cart Rate?

At SellPoints we focus on add-to-cart rate lift because it is the point where our interactive content makes the most direct difference. And we do that because add-to-cart on the product detail page is a critical point in the consumer’s buying decision. It’s hard to buy online without first adding to cart, so cart lift is an important indicator of overall conversion lift. Put another way, retailers can and do spend considerable effort sweetening the deal at checkout. But those free shipping offers, BOGO deals, and incentive discounts wouldn’t be worth much if your consumers aren’t excited to add your product to a cart to begin with.

It’s no accident then that our platform is designed to create a significant and direct boost of add-to-cart rate. We measure it, and share the results in our product page reporting. Because our expertise is in interactive experiences that increase product page performance, we have a strong interest in e-commerce analytics that show what it’s doing.

And happily, our average is a 23% boost in add to cart rate and a typical Story Point hero image solution pays for itself in a matter of days. This is across all product categories and online retailers and proven statistically through rigorous product page testing. Here are some conversion lift averages by product category:

  • Sports & Fitness +39%
  • Appliances +37%
  • Travel & Luggage +37%
  • Home Improvement +34%
  • Outdoor Recreation +31%
  • Electronics +30%

With averages like these, there are certainly brands that see even greater improvement in cart rates. What are your add-to-cart rates?

Curious what your incremental lift could be?

The beauty of this approach is you can apply it to any metric, such as checkout rate or revenue, and calculate how it would look with our average 23% increase. Though not every shopper who adds to cart will ultimately check out, the increase tends to flow through the funnel. Your business might have a 10% add-to-cart rate, and 40% of those consumers might ultimately complete checkout. The 40% checkout will remain fairly constant, so if you increase add-to-cart by 22%, you can expect a 22% conversion lift at checkout.

Want more specifics of your product category and the retailers you work with? Reach out to us!

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