# The numbers behind the EKM checkout redesign

> EKM measured our checkout overhaul at an average 38% conversion rate increase – from 13% up to 63%. The original study is offline, so I've archived the numbers here.

Published: 2026-07-25 · Author: John Slater · Canonical: https://www.slaterjohn.com/ekm-checkout-conversion-study

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EKM measured the checkout overhaul my team shipped at an average **38% conversion rate increase** across sampled shops – 13% at the lowest, 63% at the best. This post is the permanent home for those numbers.

> **Why this post exists:** My About page and CV have linked to EKM’s checkout study since it was published. That article has since disappeared from the EKM blog, so I’ve summarised it here and linked the archived copy – partly for anyone who wants the source, mostly so the numbers I quote have a proper home.

Between 2015 and 2016 my team and I completely overhauled the checkout system on the EKM platform – a project we called Optimal Checkout. It rolled out in phases to the thousands of online shops running on EKM at the time.

EKM’s research team measured the impact by comparing conversion rates on a sample of shops before and after the new checkout. They were careful about it too: the sampled shops didn’t sell seasonal goods, and data gathering was paused for the whole of Black Friday week so a good sales period couldn’t skew the comparison.

## What did the study find?

- Average conversion rate increase: **38%**
- Lowest increase in the sample: **13%** (a gas safety equipment retailer)
- Highest increase: **63%** (a plumbing supplies shop)

Every shop in the sample converted better on the new checkout. So when I say the project “increased conversion by up to 63%”, this study is where the number comes from – and it’s worth being clear that 63% was the best case, not the average. The average was 38%, which for a checkout serving millions of customers is the number I’m actually most proud of.

## Where is the original article?

The findings were published on the EKM blog as “Checkout forecast: Early predictions” by Paula Counsell, as an early preview of a larger study. The original URL is dead, but the article survives in the [Internet Archive](https://web.archive.org/web/20210307062312/https://www.ekm.com/blog/checkout-forecast-early-predictions/).

You can read about the checkout work itself in my case studies: [improving the returning customer checkout](/improving-the-checkout-experience-for-returning-customers) and [reducing nine address fields to four](/increasing-conversions-with-fewer-fields).


## Quick answers

### How much did the EKM checkout redesign increase conversion?

EKM measured an average 38% conversion rate increase across sampled shops, with the lowest at 13% (a gas safety equipment retailer) and the highest at 63% (a plumbing supplies shop).

### Where does the 63% conversion figure come from?

From EKM’s study ‘Checkout forecast: Early predictions’, which compared shop conversion rates before and after the Optimal Checkout rollout in 2015–16. 63% was the best case in the sample – the average was 38%.

### Who designed the EKM Optimal Checkout?

My team at EKM. I was the lead designer on the overhaul, and the returning-customer and address-field improvements documented in my case studies built on it.