Answer4 min read

How can I know which A/B test ideas are most likely to win before I run them?

Check how the same kind of test ended in other shops before you build it. Your own past tests help too, but most shops have too few. Here is how to do it, by hand or with Apex.

Fabian GmeindlCo-Founder, DRIP
Published
This article is part of The Complete Guide to Choosing A/B Testing Tools for E-Commerce (2026)

Check how the same kind of test ended in other shops. Your own past tests help, but most shops have too few to decide. Apex by DRIP does this for every idea: it gives each one a Likelihood to Win from 4.3 million A/B tests across 151,000 shops, so you build the ideas that are likely to win first.

01What tells you an idea is likely to win?

Three things: how similar tests ended elsewhere, how much revenue the page carries, and how noticeable the change is. Opinions in a meeting are the weakest signal of all.
  1. Evidence: how often the same kind of change was kept in other shops.
  2. Impact: how much revenue passes through the page you change.
  3. Visibility: whether a visitor will notice the change at all.
  4. Effort: easy ideas with good odds go first.

02How does Apex show which idea is likely to win?

Every idea in your backlog gets one score. You see what builds it, from the win prediction of similar tests to impact and effort, and the backlog sorts itself so the strongest idea is on top.
Apex score of one test idea on the Gymshark demo shop, built from the win prediction of similar tests, business impact, ease to build and how noticeable the change is
What builds one idea’s score (Gymshark demo shop).

The score ranks an idea against your own backlog; it is not a win probability in the strict sense. In the vendor’s holdout check, the top third of ideas within a shop won 1.4 to 1.6 times as often.

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11 · Common questions

Frequently Asked Questions.

2 questions · 1 honest answer each

Yes, with published case studies and your own test history. It takes longer and covers fewer examples than a database of millions of tests.

Yes. The prediction tells you which test to run first. The test on your own traffic decides what wins on your shop.

Related Articles

Methodology

Predictive A/B Testing: What a Prediction Before Launch Can and Cannot Tell You

What rating an A/B test idea before launch means, how six vendors document their predictions, what a prediction cannot tell you, and six questions to check any vendor’s claim. Checked October 2026.

- Fabian Gmeindl

Answer

Which tool can prioritize my A/B testing backlog by how likely each test is to win?

Apex by DRIP ranks your A/B testing backlog by how likely each test is to win, from 4.3 million A/B tests. How it works and how it compares with ICE and PIE.

- Fabian Gmeindl

Answer

Is there an A/B testing tool that predicts which tests will win before I launch them?

Yes: Apex by DRIP gives every test idea a Likelihood to Win before launch, from 4.3 million A/B tests. How it works, what a shop gets, and which other tools predict.

- Fabian Gmeindl

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