Fast home-built cart replacing hosted cart: +94% conversions
Commentary byLiftArchiveOur analysis, not theirsReplacing a slow hosted shopping cart with a fast, home-built lightbox cart lifted purchase conversions by 94%.
Patrick McKenzie ran this split test for Bingo Card Creator and reported it on the Kalzumeus (patio11) blog.
Several cart changes shipped together, so the lift can't be credited to any one of them.
- Purchase conversions: +94% for the new cart.
- In a later post the author said they had reset the test and still saw roughly a 100% improvement.
- Sample size, duration and confidence level were not shared.
The change
Fast branded lightbox cart without Update Cart or Continue Shopping steps
Simplified mockup drawn by LiftArchive from the shared screenshots.
Control
The hosted e-junkie shopping cart. It was slow to open and included Continue Shopping and Update Cart steps.
Variant
A fast lightbox-style cart built in-house, with prices calculated in the page, no Continue Shopping or Update Cart buttons, and product branding instead of shopping-cart wording. Payment was still processed by e-junkie.
Why it likely won
Our reading of the result, not the practitioner's claim.
- A cart that opens instantly gives buyers less time to hesitate or give up.
- Removing Continue Shopping and Update Cart cut steps that made no sense for a single software product.
- Branded wording may have felt more like buying the product and less like a generic store checkout.
Caveats: The results post shares only the headline number, with no sample size or confidence. Several cart changes were bundled, and Bingo Card Creator was downloadable desktop software in 2009, not SaaS.
Who ran it
Patrick McKenzie ran this test and published the results (Kalzumeus (patio11) blog). The numbers are theirs; the summary and commentary on this page are ours.
Read the original case study on Patrick McKenzie →
How to run this test on your site
- Hypothesis
- If we replace our slow, generic checkout with a fast, single-product checkout without extra cart steps, then more buyers will complete payment because there is less delay and fewer decisions.
- Primary metric
- Completed purchases per checkout start
- Guardrails
- Refund rate
- Payment errors
- Average order value
- Who should test it
- SaaS and software sellers with one main product who use a generic hosted cart. It matters less if you already use a fast, streamlined checkout built for subscriptions.
Questions
Does checkout speed affect conversions?
It can. A slow cart gives buyers a moment to reconsider, and this faster cart nearly doubled purchases, alongside other changes.
Should a single-product SaaS checkout have a Continue Shopping button?
Usually not. When there is only one thing to buy, store-style steps add clutter and choices that don't help the buyer.
Can you change the cart without changing payment processor?
Yes. In this test the cart was rebuilt in-house while the same processor still handled payment.