About one in eight times. Rewriting the words on a button wins 12% of the time. For comparison, changing that same button's **colour** won 16% in our data — though on a much smaller sample, so do not read too much into the ordering.
A middling bet with a good payoff when it lands: the median winner moves +21.8%.
| Tests analysed | 250+ |
| Beat control | 12% |
| No measurable difference | 68% |
| Lost to control | 20% |
| Median lift when it won | +21.8% |
Typical winning range: +8.8% to +54.2% for the middle half of winners. Median traffic per variant was 1412 visitors. Most ran on homepages (120), product pages (48), lead capture pages (38).
The button's words change. Size, colour and position stay as they were. Change the colour too and you have two variables.
Adjacent categories, and how often they win: layout (19%), hero image (17%), styling (15%).
| page type | win rate | tests |
|---|---|---|
| homepages | 11% | 100+ |
| product pages | 6% | 48 tests |
| lead capture pages | 21% | 38 tests |
| landing pages | 10% | 31 tests |
Only page types with at least 30 CTA 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.
Button copy only reaches people who have already scrolled to the button and are deciding. That is a narrower audience than a hero or layout change reaches, which caps how much it can move.
| 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 (this page) | 12% | 315 |
| Body copy | 11% | 337 |
| Split URL | 11% | 1164 |
| Headline | 10% | 918 |
| Social proof | 9% | 196 |
The winners here do not settle it. Both specific and generic labels appear among them, and among the failures.
On these numbers, no — layout wins 19% against CTA copy's 12%. Test the cheaper one first only if the traffic makes the better one unreadable.
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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