Detects A/B testing tools and experiments on the website
Users
399
+9 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
13
0 in 30 days
Store rank
#48K
#40K among extensions
Version
3.0.2
updated 14 Oct 2026
Users
monthly, 16 months
Latest, 16 Oct 2026:399 usersMove the mouse over the chart for any month
Ratings count
monthly, 16 months
Latest, 16 Oct 2026:13 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About Welyft I A/B Tests identifier
Detect A/B tests, personalization and the CRO stack of any website, and check results with a built-in confidence calculator.
Description
See which experiments and personalization campaigns run on the page you are viewing, which variation you have been assigned, and what the site's conversion stack is made of. Built for CRO, UX and analytics teams, with a statistical calculator to check your own results.
π Features
β’ Experiments from 25 platforms, including Optimizely, AB Tasty, VWO, Kameleoon and Dynamic Yield: name, ID, type (A/B, A/A, split URL, multivariate, patch, personalization) and your variation β’ Server-side support, when the platform exposes it in the browser β’ Stack overview: the analytics, UX analytics, consent and marketing tools used by the site β’ Live mode: follow new exposures as you browse, with an optional notification for each one β’ Side panel that stays open while you browse, in light or dark theme β’ Cookie reset to get assigned a new variation β’ Confidence calculator β Results: frequentist (z-test, Bonferroni correction, always-valid p-value) or Bayesian (probability to beat control, probability to be best), with sample ratio mismatch and sample size alerts β Planning: minimum detectable effect and recommended duration β Sequential analysis: log daily totals and see when a winner can be called β Full-screen view with charts, plain-language explanations, examples, JSON export and import
π Privacy
Everything runs locally in your browser, and nothing is sent by default. On first use, you can opt in to share anonymous scan data for aggregated adoption statistics: the website domain and page address (without query parameters), the names, IDs and types of the campaigns found, the tools found and the extension version. No personal data, cookies, form data or browsing history beyond scanned pages is ever transmitted. Sharing can be turned off at any time from the extension footer. Figures entered for statistical checks stay on your device. Privacy policy: https://www.welyft.com/en/politique-de-confidentialite
β FAQ
How does it work? It reads the public front-end APIs exposed in the browser for debugging. It is read-only and only shows what they make public: campaign name, type and assigned variation. Audiences, targeting rules and performance data are never accessible.
Which platforms are supported? 25 in total. For the main ones, you get the full details; for the others, the extension shows that it is installed on the site.
Why is nothing showing up? β’ Cookie consent not granted: some tools only load after consent β’ Presence-only support: the solution is identified, without details β’ Server-side setup that exposes nothing in the browser β’ No campaign running on this page β’ Late loading: the side panel refreshes automatically, or click Reload
π Changelog 3.0.1: Interface, live mode overlay and notifications available in French 3.0: Confidence calculator, 25 platforms, stack overview, redesigned interface with light and dark themes, more reliable with multiple tabs and late-loading scripts 2.0: Side panel, server-side support, live mode, exposure notifications, cookie reset, anonymous statistics opt-in 1.2: Bug fixes
Growth
Window
Users
Change
Ratings
Rating
7 days
β5
β1.2%
0
0.00
30 days
+9
+2.3%
0
0.00
6 months
+31
+8.4%
β1
0.00
1 year
+40
+11.1%
β2
0.00
Chrome Web Store search rankings
Where Welyft I A/B Tests identifier appears when people search the store, with the 30 day change