More often than changing the words next to them. Swapping the main visual wins 17% of the time. Rewriting the headline on the same page wins 10%. If you are choosing between the two on a homepage, the image is the better bet.
The hero is the first thing anyone sees, so replacing it changes the whole first impression rather than one line of it.
| Tests analysed | 100+ |
| Beat control | 17% |
| No measurable difference | 65% |
| Lost to control | 18% |
| Median lift when it won | +19.4% |
Typical winning range: +8.7% to +31.8% for the middle half of winners. Median traffic per variant was 1601 visitors. Most ran on homepages (68), product pages (27), landing pages (24).
The main visual is swapped, cropped or replaced. Surrounding copy stays as it was.
Adjacent categories, and how often they win: layout (19%), styling (15%), CTA copy (12%).
| page type | win rate | tests |
|---|---|---|
| homepages | 18% | 50+ |
Only page types with at least 30 hero image 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.
A visitor forms an impression of the page before reading it. The hero image is most of that impression, which gives an image swap more room to move behaviour than a headline rewrite in the same position.
| change type | win rate | tests |
|---|---|---|
| Layout | 19% | 351 |
| Hero image (this page) | 17% | 160 |
| Form | 16% | 81 |
| CTA colour | 16% | 32 |
| Styling | 15% | 1414 |
| Price framing | 13% | 117 |
| CTA copy | 12% | 315 |
| Body copy | 11% | 337 |
| Split URL | 11% | 1164 |
| Headline | 10% | 918 |
| Social proof | 9% | 196 |
Our data does not answer this. The winners in this set moved in different directions on different sites, and there is no general rule in them.
Yes, where the background is the page's main visual. A decorative texture change is a styling test instead.
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.
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