How HENSSLERS increased conversions by +4.3% with Speed Kit
Published on November 1, 2026
- General Consumer Goods
- Europe
- Shopify
+4.3%
Conversion rate uplift from faster page loads
38%
Faster median LCP on accelerated pages
70%
Faster Time to First Byte
“We wanted the 50/50 test to speak for itself before making any decision. It did. You notice the speed as soon as you navigate through the shop, and the numbers back it up. That made the decision to work with Speed Kit an easy one.”
Introduction
HENSSLERS is the online shop of Steffen Henssler's brand. It sells cookware such as pans, knives and pots alongside spices, oils, sauces and pasta, and offers recipes for its community. Almost 500,000 customers trust HENSSLERS, and the shop delivers to Germany, Austria and Switzerland. It runs on Shopify.
Challenge
HENSSLERS runs its shop without developers in-house and works with a freelance Shopify developer. A speed project therefore had to be light to set up and fit the shop as it is. And the team wanted the decision on Speed Kit to rest on a test against a control group, in HENSSLERS' own numbers.
Solution
Speed Kit came to the shop as a Shopify app, installed by the HENSSLERS team during the kick-off call. It works out which page a visitor is likely to open next and prepares it in the background, so that page is often ready before the click. After configuration and a QA phase, Speed Kit went live on a small share of traffic first and then ran as a PoC phase, with half of the visitors in an unaccelerated control group. After the PoC phase, HENSSLERS switched Speed Kit on for all of its traffic.
Results
Speed Directly Drives Commercial Results: Speed Kit's impact charts group real sessions on the shop by how fast their pages loaded. On HENSSLERS, every 100 ms of faster Largest Contentful Paint goes with a 1.41% higher conversion rate and a 2.1% higher add-to-cart rate, and sessions get longer as well. With the acceleration Speed Kit delivered, that comes to a 4.3% higher conversion rate, a 6.4% higher add-to-cart rate and 10.6% longer sessions.
Performance Improvements — Largest Contentful Paint (LCP): During the PoC phase, half of the visitors got Speed Kit and the other half did not. For the Speed Kit group, the main content appeared 38% faster at the median on accelerated pages and the first byte arrived 70% sooner. Category pages gained the most at 53%, product pages 35% and recipe pages 30%.
Predictive Preloading Coverage: Speed Kit prepares the next page before the customer clicks. 78% of next pages are cached before the users visit them, and 44% of users get a page that was prerendered in the background.
Conclusion
HENSSLERS wanted the test to speak for itself. With Speed Kit, main content loads 38% faster on accelerated pages, 78% of next pages are cached before the click, and faster pages lift the conversion rate by 4.3%. HENSSLERS has since switched Speed Kit on for all of its traffic.
