All WCAG criteria
WCAG 2.1·Understandable·3.3 Input Assistance

3.3.1 Error Identification

Level A

When a form input is rejected, the error must be identified in text.

Why it matters

Color-only error indicators exclude colorblind users; non-text indicators exclude screen readers.

Common failure
<input class="error">
Accessible version
<input aria-invalid="true" aria-describedby="email-err">
<span id="email-err">Email format is invalid</span>

How OnlyEnable handles this

Source-code fix required. No widget can solve this — it requires changes to your content or markup. Our remediation team can help.

Related criteria in 3.3 Input Assistance