⚡ Free · no signup · no app install · read-only
Your A/B test hides the whole page to stop the flicker. For how long?
Every client-side A/B tool faces the same choice: hide the page until the variant is ready, or let visitors see the original first. We read your storefront as served and show you which side of that trade you are on, and what it costs.
Based on publicly available data only. Informational, not legal advice.
What this checks
- Which experimentation tool is on your storefront — VWO, Optimizely, Convert, AB Tasty, Intelligems, Visually, Shoplift, Adobe Target and a dozen more
- Whether an anti-flicker snippet hides the page before it paints, and which element it hides
- The fallback timeout — the worst case for how long a visitor stares at nothing
- Experiment scripts loaded synchronously in <head>, where they block rendering
- Hiding snippets left behind after the tool was removed (Google Optimize is the usual culprit)
- The download weight of the experiment library and whether its origin is preconnected
- Signs that a test runs Shopify-side or in the theme instead of by rewriting the DOM
FAQ
Flicker or a hidden page — which is actually worse?
Neither is free. Hiding the page means your largest element cannot paint until the tool releases it, so you are trading Largest Contentful Paint for a clean swap. Letting it flicker keeps LCP intact but shows the control to people you meant to put in the variant, which quietly biases the result. This tool tells you which one you chose and how big the bill is; it does not tell you which is right for your store.
Why do some checks say 'could not tell'?
We read the HTML exactly as your server returned it and we do not run JavaScript. So a library URL that the snippet assembles at runtime, or a timeout buried inside a minified vendor bundle, is genuinely out of reach. Those items say so instead of guessing. The one thing this limit does not hurt is the anti-flicker check itself: a hiding snippet has to be inline in the served head to work at all, so if it is not there, it is not running.
My testing tool is installed through GTM or a Shopify app embed. Will you see it?
Partly. The container tag and the app embed's own script show up in the source, and any hiding snippet must be there too. But a tool that GTM injects only after the container loads will not be named — we will report what we saw and mark what we could not.
Want the tests to keep running without the speed tax?
We are a Shopify studio. The audit is free; the fix is yours to make — or ours to ship.