Skip to main content
Understandable WCAG 3.1.5

3.1.5 Reading Level

When text requires more than a lower secondary education reading level, supplemental content or an alternative version is available.

Level AAA Minor WCAG 2.0 (new) WCAG 2.1 WCAG 2.2

What this rule means

WCAG 3.1.5 requires that when text content is more complex than a lower secondary education reading level (roughly ages 12-14, or grades 7-9), a supplemental version is provided. This could be a simplified summary, illustrations, or a plain-language version.

This applies after removing proper names and titles. The goal is to ensure content is accessible to people with reading disabilities, cognitive disabilities, or limited education.

Why it matters

Complex language excludes people with dyslexia, cognitive disabilities, lower literacy levels, and non-native speakers. Government and healthcare content, in particular, must be understandable to the widest possible audience.

Simplified alternatives benefit everyone — even highly literate readers prefer clear, concise content. Studies show that plain language reduces errors and increases task completion rates.

Related axe-core rules

There are no automated axe-core rules for this criterion. Reading level assessment requires specialized tools or manual evaluation.

How to test

  • Use readability scoring tools (Flesch-Kincaid, Gunning Fog, Coleman-Liau) to assess content complexity.
  • Identify content that scores above the target reading level.
  • Verify that supplemental content or simplified alternatives are provided for complex sections.
  • Test with users from the target audience to confirm comprehension.

How to fix

Provide simplified alternatives for complex content:

  • Write a plain-language summary at the top of complex documents.
  • Use illustrations, diagrams, and infographics to supplement text.
  • Break long sentences into shorter ones (aim for 15-20 words per sentence).
  • Replace jargon with everyday words where possible.
  • Provide an "Easy Read" version of critical documents.

Common mistakes

  • Assuming that all visitors have the same reading ability.
  • Using unnecessarily complex vocabulary when simpler alternatives exist.
  • Writing in passive voice, which increases reading difficulty.
  • Failing to provide plain-language summaries for legal or technical documents.

Resources