How premiumXL increased its conversion rate by 3% with Speed Kit
Published on November 5, 2026
- Furniture & Homeware
- Europe
- Shopify
+3%
Relative uplift in user conversion rate during the PoC phase
85%
Of next pages preloaded before the click
−505 ms
LCP improvement on accelerated pages
“Most of our visitors come to us from a Google ad. They are looking for something specific and don't know us yet, so if the page takes long, they lose patience. The PoC brought really good results, and we wanted to switch Speed Kit on for all of our traffic as quickly as possible.”
Introduction
premiumXL sells furniture, decor and home accessories online, for indoors and outdoors, with the conviction that good furniture does not have to be expensive. Most products are in stock in premiumXL's own warehouses in Emsdetten and Osnabrück, which ship more than a million parcels a year. The shops run on a single Shopify Plus instance, with a separate domain for each European market and premiumxl.de as the largest.
Challenge
Around eight in ten visitors reach premiumXL through a Google ad. They are searching for a specific product, often don't know the brand yet, and a slow page tests their patience before the shop has a chance to make an impression. premiumXL builds most things itself with a small in-house team instead of an agency, and changes often go straight into the live theme. A faster store had to come without a development project on the Shopify side, and with its own way of measuring the effect, since premiumXL has no A/B testing tool.
Solution
Speed Kit runs alongside the existing Shopify Plus store. It works out which page a visitor is likely to open next and prepares it in the background, so that page is often already complete in the browser when the customer clicks. During the PoC phase on premiumxl.de, half of the visitors got Speed Kit and the other half formed an unaccelerated control group, measured with Speed Kit's own real-user monitoring. After the results, premiumXL switched Speed Kit on for all visitors on premiumxl.de.
Results
Business Impact — PoC Phase: During the PoC phase, half of the visitors on premiumxl.de got Speed Kit and the other half, the control group, did not. The Speed Kit group reached a 3.09% higher user conversion rate, placed 3.27% more orders and generated 3.08% more revenue.
Performance Improvements — Largest Contentful Paint (LCP): On the accelerated pages, the main content reaches the customer 505 ms, or 41%, faster. Category pages gain the most at 69%, the home page 65% and product pages 29%, and the first byte arrives 35% sooner.
Predictive Preloading Coverage: Speed Kit prepares the next page before the customer clicks. 85% of next pages are cached before the users visit them, and 46% of users get a page that was prerendered in the background.
Conclusion
premiumXL wanted a faster store for visitors who arrive from an ad and decide within seconds, without a development project and with a measurable result. With Speed Kit, main content loads 41% faster on accelerated pages, 85% of next pages are cached before the click, and during the PoC phase the Speed Kit group converted at a 3% higher rate. premiumXL has since switched Speed Kit on for all visitors on premiumxl.de.
