Accessibility is often treated as compliance work that sits apart from CRO. It shouldn’t be: every barrier that stops a disabled user also slows down someone on a cracked phone, in bright sunlight or holding a baby.
The checks that matter most for conversion
All references are to WCAG 2.2 (W3C).
| Issue | WCAG | Conversion impact |
|---|---|---|
| Text contrast below 4.5:1 | 1.4.3 | Prices, labels and terms become hard to read |
| Inputs without visible labels | 3.3.2 | Users forget what a field is for, especially on mobile |
| Errors only shown in colour, or vaguely | 1.4.1, 3.3.1, 3.3.3 | Users can’t tell what went wrong at checkout |
| Tap targets smaller than 24×24 px | 2.5.8 | Mis-taps on mobile buttons and links |
| Keyboard traps and invisible focus | 2.1.2, 2.4.7 | Keyboard and switch users can’t finish |
| Content that moves or times out | 2.2.1, 2.2.2 | Carousels and timers that users can’t control |
Make it part of Validate
Add these to every test’s QA checklist:
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Don’t let a test exclude people
A variant that breaks keyboard access for half the test’s duration excludes people from buying. Treat accessibility failures like functional bugs: fix before launch.