---
title: "What is A/B test? | Chargezen"
description: "An A/B test sends two or more versions of a message to small groups, measures which performs better, and sends the winner to everyone else."
url: "https://chargezen.com/glossary/ab-testing"
lang: "en"
---

Canonical URL: https://chargezen.com/glossary/ab-testing

# A/B test

A/B test (split test)

Email Marketing

An A/B test sends two or more versions of a message to small groups, measures which performs better, and sends the winner to everyone else.

## What is A/B test?

An A/B test changes one thing, such as the subject line, offer or button, and lets results decide. **Pick the right measure:** opens for subject lines (with care, because of Apple Mail Privacy Protection), clicks for content, and orders for offers. **In SmartyTap,** email and text campaigns can test up to seven versions. You set the test size (10% to 100%), pick the winner by open rate, click rate or placed order rate (texts use placed order rate) and the test length (1 to 72 hours); the winner then sends to everyone else automatically. SmartyTap compares whole versions and doesn't run multivariate tests.

## Example

A store tests "Free shipping today" against "Your weekend treat" on 20% of its list for 6 hours; the winner by clicks goes to the other 80%.

## Why A/B test Matters

Each test replaces a guess with evidence, and the lessons carry into every campaign after.

## A/B test FAQ

How big should an A/B test be?

Big enough that each version reaches a few hundred people. With a small list, test on a larger share or split the whole list.

Can I test more than one change at once?

You can, but you won't know which change made the difference. Change one thing per test.

## Explore More Terms

Browse our complete glossary of e-commerce and subscription terms.

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