Level AAASince WCAG 2.0
2.3.2 Three Flashes
Guideline 2.3: Seizures and Physical Reactions – Nothing flashes or moves in a way that can make people ill.
What does the rule require?
Nothing ever flashes more than three times per second – with no exception for small or dim areas.
How to get it right
Remove all rapid flashing, even in small areas of the picture.
Who benefits most?
- People with epilepsy
Official wording
This page explains the rule in simple words. Only the original W3C text is normative.
- “Understanding Three Flashes” at W3C (external site)
- Techniques in the WCAG Quick Reference (external site)