Rarely, and rarely by much. Body copy changes win 11% of the time — the **lowest rate of any category with a meaningful sample**. Nine in ten produce no measurable difference at all.
The weakest bet in this benchmark. If you are testing body copy because you cannot think of anything else to test, that is worth noticing.
| Tests analysed | 250+ |
| Beat control | 11% |
| No measurable difference | 76% |
| Lost to control | 13% |
| Median lift when it won | +10.9% |
Typical winning range: +5.8% to +22.8% for the middle half of winners. Median traffic per variant was 1372 visitors. Most ran on product pages (109), homepages (100), landing pages (29).
Supporting paragraph text is rewritten, shortened or expanded. Headings, images and CTAs are untouched.
Adjacent categories, and how often they win: layout (19%), hero image (17%), styling (15%).
| page type | win rate | tests |
|---|---|---|
| product pages | 9% | 100+ |
| homepages | 14% | 100+ |
Only page types with at least 30 body copy tests appear here.
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.
Body copy sits below the elements people actually read, and it is read by the smallest share of visitors of anything on the page. A change that most of your traffic never sees cannot move most of your traffic.
| change type | win rate | tests |
|---|---|---|
| Layout | 19% | 351 |
| Hero image | 17% | 160 |
| Form | 16% | 81 |
| CTA colour | 16% | 32 |
| Styling | 15% | 1414 |
| Price framing | 13% | 117 |
| CTA copy | 12% | 315 |
| Body copy (this page) | 11% | 337 |
| Split URL | 11% | 1164 |
| Headline | 10% | 918 |
| Social proof | 9% | 196 |
Both appear among the winners and the failures here. Length is not the variable this data can settle.
Headline copy is close, at 10%. The pattern across both is that copy changes trail position and visual changes.
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.
Mida.so is a super lightweight A/B testing tool to help you experiment, analyze and implement conversion strategies in minutes.
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