A/B testing benchmarks

What actually wins, from thousands of real A/B tests run on Mida and concluded between August 2023 and August 2026. A win means the variant beat its control with a statistically significant result.

By what you change

change type	win rate	tests
Layout	19%	250+
Hero image	17%	100+
Form	16%	50+
CTA colour	16%	32 tests
Styling	15%	1,000+
Price framing	13%	100+
CTA copy	12%	250+
Body copy	11%	250+
Split URL	11%	1,000+
Headline	10%	500+
Social proof	9%	100+

By industry

industry	win rate	variants
E-commerce	14%	1840
SaaS / Software	9%	726
Professional Services	14%	496
Finance & Insurance	16%	428
Education	10%	422
Health & Wellness	15%	361
Media & Publishing	15%	199
Marketplace	12%	191
Travel & Hospitality	11%	131
Healthcare	8%	110
Nonprofit	15%	40

Industry comes from the verified domain the Mida pixel fired on, covering 97.8% of tested variants — not from a self-reported field, which disagrees with it 65% of the time.

Read the method before the numbers

Most tests do not win, and most of what gets tested never moves anything. We exclude tests that never got enough traffic to say anything either way, because a flat result on too little traffic is not evidence a change failed. The methodology page states exactly what we exclude and what these numbers cannot tell you.

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.