Do styling A/B tests work on checkout pages?

About the same as anywhere else. Styling tests win 11% of the time on checkout pages, against 15% across all page types. This page neither helps nor hurts the change type.

It is also the strongest change type we can measure on checkout pages — nothing else we track wins more often there.

Small sample. Few of these tests cleared the bar. The 95% interval on that win rate runs 5% to 23%, so read the figure as directional.

The numbers

	checkout pages	all page types
Tests analysed	47 tests	1,000+
Beat control	11%	15%
No measurable difference	77%	—
Lost to control	13%	—
Median lift when it won	not reported	—

Median traffic per variant was 1904 visitors.

What else is worth testing on checkout pages

change type	win rate on checkout pages	tests
Styling (this page)	11%	47 tests

Only change types with at least 30 tests on checkout pages appear here.

What counts as a styling test

Visual treatment shifts — spacing, weight, borders, colour, shadows — with the same content in the same order. Move the content and it is a layout test. Rewrite it and it is a copy test.

Control and variant wireframe for a styling A/B test — Control on the left, variant on the right. For how this differs from adjacent categories, see the styling benchmark.

Styling tests that won on checkout pages

Hides one test class, shows another, widens the basket block, and centers a static-block widget with flex layout
Forces the bump-stl element to be visible by setting display to block
Adjusts font size, color, spacing, and line height of the payment note text without changing its wording
styles layout/appearance of an existing testimonial block below the CTA (avatar+text alignment, sizing, responsive stacking) without changing its wording

Styling tests that did not

Adds a CSS class to the body element, presumably enabling alternate payment-related styling, with no visible content change described in the code.
hides several sections/divs on the page without changing any wording
Hides the recommendation container/widget elements from the page

These are individual tests, not rules. Each ran on one site, with one audience, against one page we are not showing you. They are picked to be illustrative rather than sampled at random, and a change that won here can lose on your page for reasons none of this captures. Read them as prompts for what to test, not as findings to copy.

Who ran these tests

This is every Mida account that ran a readable test — in-house marketers, founders, product teams, and agencies working on client sites. Nothing here is filtered by who ran the experiment or how experienced they are.

Low win rates are normal in experimentation, including at the top end. Microsoft's experimentation team, reporting on its own platform, found that only about one third of ideas improve the metric they were designed to improve — and that roughly another third actively hurt it. That is a dedicated experimentation organisation with research, prioritisation and review behind every test.

A mixed population like this one runs below that. The gap is roughly what disciplined practice buys you: ideas grounded in research rather than opinion, one variable at a time, and tests built so the result can actually be read.

So treat these as a general base rate, not a target. If you would rather not close that gap the slow way, find a CRO agency in the United States, the United Kingdom, the Netherlands or Australia — or browse every region.

A win is a variant that beat its control on that test's primary goal with a statistically significant result. Tests that never got enough traffic to say anything either way are excluded. The methodology has the full detail, including what these numbers cannot tell you.