Level ASince WCAG 2.0
3.3.1 Error Identification
Guideline 3.3: Input Assistance – Forms help people avoid and correct mistakes.
What does the rule require?
When input is wrong, text says which field is affected and what is wrong. A red border alone is not enough.
How to get it right
Show the message right at the field: “Email address: please include an @ sign” and connect it with aria-describedby.
Who benefits most?
- Blind people
- People with cognitive disabilities
- People with colour vision deficiency
Official wording
This page explains the rule in simple words. Only the original W3C text is normative.
- “Understanding Error Identification” at W3C (external site)
- Techniques in the WCAG Quick Reference (external site)