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Success Criterion · WCAG 2.3.1

Three Flashes or Below Threshold

Web pages do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds.

Level AWCAG 2.0Operable2.3 · Seizures and Physical Reactions

Success criterion

What WCAG 2.3.1 requires

Summarized directly from the official Understanding document so teams can quote the requirement accurately.

All non-text content that is presented to users must expose an equivalent text-based alternative unless a documented exception applies.

View Understanding 2.3.1 Open QuickRef techniques

Overview

Use this space to describe how your product interprets this success criterion, list ownership, and capture implementation decisions for future audits.

Reference: All summaries and highlights originate from Understanding WCAG 2.3.1 and the W3C quick reference.

Read the Understanding doc View sufficient techniques

Fast facts

Conformance level: Level A
WCAG version introduced: WCAG 2.0
Principle: Operable
Guideline: 2.3 · Seizures and Physical Reactions

Implementation checklist

Capture progress and blockers

Document how this criterion impacts your product and note any exceptions.
Describe the user experience goal in plain language for designers and engineers.
List the components, templates, or workflows that must meet this requirement.
Capture manual and automated testing steps for future audits.

Testing ideas

Prove conformance with evidence

Pair automated linting with human review to verify visual, auditory, or temporal aspects.
Use assistive technology walkthroughs (screen reader, keyboard, switch, voice) to validate behavior.
Capture screenshots or recordings that demonstrate pass/fail conditions.