A/B Test

Design statistically valid A/B tests with clear hypotheses, proper sample sizing, and analysis plans.

A Claude Code skill that builds complete split test plans — hypothesis, sample size, variant design, traffic allocation, and pre-committed analysis criteria.

/ab-test design an A/B test plan a split test

How it works

1

Test Context

The skill asks what you want to test, why, where, current performance baseline, success metrics, and minimum detectable effect.

2

Hypothesis & Sample Size

Builds a structured hypothesis and calculates required sample size and test duration based on your traffic and baseline conversion rate.

3

Variant Design & Allocation

Designs control and variant(s) with specific changes, traffic allocation strategy, and guardrail metrics to monitor.

4

Analysis Plan & Export

Pre-committed analysis plan with decision criteria, saved as a structured markdown document — no post-hoc rationalization.

Why use it

Structured Hypotheses

Clear 'if-then-because' hypotheses that make test results actionable regardless of outcome.

Sample Size Calculations

Proper statistical sizing based on baseline rate, desired lift, and significance level — no guessing.

Pre-committed Analysis

Decision criteria defined before the test runs — preventing p-hacking and post-hoc rationalization.

Guardrail Metrics

Secondary metrics monitored to catch unexpected negative effects on other parts of the funnel.

Use Cases

Headline Testing

Test headline variations with proper statistical rigor instead of gut feelings.

CTA Optimization

Test button copy, placement, and design with pre-committed success criteria.

Pricing Experiments

Test pricing changes, tier structures, or billing options with controlled experiments.

Layout Changes

Test page layout and information hierarchy changes with proper sample sizing.

Onboarding Flows

Test different onboarding sequences with activation rate as the success metric.

Email Subject Lines

Test email subject lines with statistically valid sample sizes and clear winners.

How to start

Install the skill in Claude Code, then trigger it with any of these phrases:

/ab-test
design an A/B test
plan a split test
set up an experiment