WCAG 2.3.1 · Level A · WCAG 2.0
Three Flashes or Below Threshold
Content must not flash more than three times per second, or must stay below the general flash and red flash thresholds.
- Principle
- Operable
- Guideline
- Seizures and Physical Reactions
- Level
- A
- Added in
- WCAG 2.0
What it means
Content must not flash more than three times per second, or must stay below the general flash and red flash thresholds.
This is the short summary — a long-form breakdown (with code examples, common failures, and fix patterns) is queued for this criterion. In the meantime, the official W3C document linked at the end of the page is the authoritative source.
Quick checks
- Run axe DevTools against the page and filter for rules citing 2.3.1.
- Navigate the component with Tab + Enter only and confirm nothing is orphaned.
- Inspect the accessibility tree in DevTools (Accessibility pane in Chrome/Firefox).
Further reading
The authoritative source is the official W3C Understanding document for 2.3.1. Framework-specific patterns and axe-rule mappings land here as the library grows.