The 2025 TestParty Guide to WCAG 3.1.5 – Reading Level (Level AAA)

Why did the accessibility specialist bring a dictionary to the website review? Because they knew that if users need one too, you're failing WCAG 3.1.5!

WCAG 3.1.5 Reading Level requires that when content demands advanced reading skills (beyond lower secondary education), you must provide an easier-to-read alternative, summary, or supplemental content. This Level AAA criterion ensures that people with reading difficulties, cognitive disabilities, or limited education can still access your information.

Table of Contents

• What WCAG 3.1.5 Requires
• Why This Matters
• Quick Implementation Guide
• Common Mistakes to Avoid
• How to Test for WCAG 3.1.5
• How TestParty Helps
• FAQs

What WCAG 3.1.5 Requires

WCAG 3.1.5 mandates that text requiring reading ability more advanced than lower secondary education level (approximately 9 years of school, or ages 14-15) must be accompanied by one of the following:

• Supplemental content that explains the complex text in simpler terms
• An alternative version written at or below the lower secondary reading level
• Visual illustrations, pictures, or symbols that clarify complex ideas
• Audio or sign language versions that convey the same information

Key exceptions:

• Proper names and titles are excluded from the reading level calculation
• Technical documentation where advanced terminology is essential may still need supplemental explanations
• Content where simplification would fundamentally change the meaning still requires alternatives

What's affected:

• Body text, articles, and long-form content
• Instructions and help documentation
• Legal notices, terms of service, and policies
• Educational materials and training content

Why This Matters

Approximately 54% of U.S. adults read below a 6th-grade level, and millions of people worldwide have dyslexia, cognitive disabilities, or are non-native speakers. Complex text creates an insurmountable barrier for these users, effectively locking them out of essential information, services, and opportunities.

While WCAG 3.1.5 is Level AAA (not required for most legal compliance), it aligns with Section 508 requirements for plain language and supports EN 301 549 cognitive accessibility provisions. The European Accessibility Act emphasizes comprehensibility, and many government agencies mandate plain language by policy. Organizations serving diverse populations—healthcare, government, education, financial services—increasingly adopt AAA criteria to ensure equitable access.

The business case is compelling: simpler content improves comprehension for everyone, reduces support costs, increases task completion, and expands your addressable audience. Plain language isn't dumbing down—it's opening up.

Quick Implementation Guide

1. Write at an appropriate reading level

Aim for 8th-grade reading level or lower for general audiences. Use short sentences (15-20 words), common words, and active voice.

2. Provide plain-language summaries

Add a "Summary" or "Plain Language Version" section before or alongside complex content:

<article>
  <div class="plain-language-summary" role="complementary" aria-label="Plain language summary">
    <h2>Summary in Plain Language</h2>
    <p>This policy explains how we protect your personal information. 
    We collect your name and email when you sign up. We never sell your data 
    to other companies. You can delete your account anytime.</p>
  </div>
  
  <div class="full-policy">
    <h2>Complete Privacy Policy</h2>
    <p>This Privacy Policy delineates the methodologies employed by [Company] 
    to aggregate, utilize, and safeguard personally identifiable information...</p>
  </div>
</article>

3. Use visual aids

Supplement complex processes or concepts with diagrams, flowcharts, icons, or illustrations. Ensure these visuals have appropriate alt text.

4. Offer multimedia alternatives

Provide audio narration or video explanations for dense text. Sign language interpretation helps Deaf users who may have different reading patterns.

5. Structure content for scannability

Use clear headings, bullet points, and white space. Break long paragraphs into shorter chunks. This helps all readers, especially those with cognitive disabilities.

Key WCAG techniques: G86 (text summaries), G103 (visual illustrations), G79 (spoken versions), G153 (easier-to-read text), G160 (sign language versions).

Common Mistakes to Avoid

Assuming everyone reads at your level

Developers and content creators often write for their peers, using jargon and complex sentence structures. Your audience is more diverse than you think.

Hiding plain-language versions

If you provide an easier alternative, make it prominent and easy to find. Don't bury it in a footer link labeled "Accessibility version."

Using readability scores as the only measure

Automated readability formulas (Flesch-Kincaid, SMOG) are helpful but imperfect. They don't account for jargon, cultural context, or logical flow. Human review is essential.

Oversimplifying to the point of inaccuracy

Plain language doesn't mean leaving out important details. It means presenting them clearly. Legal and technical accuracy must be preserved.

Forgetting to update simplified versions

When you update the main content, update the plain-language summary too. Outdated alternatives create confusion and potential legal issues.

How to Test for WCAG 3.1.5

Manual readability assessment:

• Run body text through readability calculators (Hemingway Editor, Readable, or built-in tools in Word/Google Docs)
• Target Flesch-Kincaid Grade Level of 8 or below for general content
• Exclude proper names and titles from the calculation

Content review checklist:

• Are sentences under 20 words on average?
• Is vocabulary appropriate for a general audience?
• Are complex terms defined or explained?
• Is a plain-language summary or alternative provided for advanced content?

User testing:

• Test with people who have cognitive disabilities or reading difficulties
• Observe where users struggle to understand content
• Ask users to explain what they read in their own words

Automated scanning limitations:

Most automated accessibility tools cannot reliably test WCAG 3.1.5. Readability requires semantic understanding, context, and judgment. Tools can flag potentially complex text for human review but cannot determine compliance.

How TestParty Helps

WCAG 3.1.5 is inherently difficult to automate because reading level assessment requires understanding content meaning, audience, and context. TestParty approaches this criterion through a combination of automated flagging, AI-assisted analysis, and guided human review.

What TestParty detects:

TestParty's content analysis engine scans body text and calculates readability metrics (Flesch-Kincaid Grade Level, Gunning Fog Index, SMOG) across your site. It flags pages where:

• Average reading level exceeds 9th grade (lower secondary education)
• Sentence length consistently exceeds 25 words
• Passive voice usage is high
• Technical jargon appears without definitions or glossaries
• No plain-language summary or alternative version is detected

TestParty identifies structural patterns that correlate with reading difficulty: long paragraphs without headings, dense legal or technical sections, and absence of visual aids or multimedia alternatives.

How TestParty suggests improvements:

For flagged content, TestParty's AI generates:

• Plain-language summaries of complex sections, which human reviewers can refine and approve
• Sentence simplification suggestions that preserve meaning while reducing complexity
• Vocabulary alternatives replacing jargon with common terms
• Structural recommendations for breaking up dense text with headings, lists, and white space

TestParty surfaces these suggestions in context, showing the original text alongside the proposed simplified version. Content authors review, edit, and approve changes before they're committed—ensuring accuracy and preserving brand voice.

For sites with recurring content patterns (e.g., product descriptions, help articles, legal pages), TestParty can apply approved simplification templates at scale, then flag exceptions for human review.

Developer and content workflow integration:

TestParty integrates readability checks into your content management and publishing workflows:

• CMS plugins for WordPress, Contentful, and other platforms display real-time readability scores as authors write
• Pre-publish gates flag content exceeding target reading levels before it goes live
• Pull request annotations alert developers when code changes introduce complex instructional text or error messages

This shift-left approach catches readability issues during content creation, not after publication.

Ongoing monitoring and reporting:

TestParty's dashboard tracks reading level trends across your site over time:

• Average reading level by page type, section, or content author
• Percentage of pages with plain-language alternatives
• Readability regression alerts when updates increase complexity

Audit-ready reports document your plain-language efforts for compliance reviews, procurement requirements, or internal accessibility goals.

Because WCAG 3.1.5 is Level AAA, TestParty allows you to configure whether readability violations are flagged as warnings or blockers, giving you control over your compliance targets.

Limitations and human judgment:

TestParty emphasizes that reading level compliance requires human expertise. The platform guides and accelerates the process but doesn't replace content strategists, plain-language specialists, or user testing. TestParty flags potential issues, suggests improvements, and tracks progress—but humans make the final call on whether content is truly understandable for your audience.

FAQs About WCAG 3.1.5

What is WCAG 3.1.5 in plain language?

WCAG 3.1.5 says that if your content is hard to read (requires more than about 9 years of education), you need to provide an easier version, a summary, or other help like pictures or audio. This ensures people with reading difficulties can still understand your information.

Is WCAG 3.1.5 required for ADA compliance?

No. WCAG 3.1.5 is Level AAA, and ADA compliance typically requires only Level AA conformance. However, government agencies, healthcare organizations, and educational institutions often adopt plain-language policies that align with this criterion, and it's considered best practice for inclusive design.

What reading level should I target?

For general audiences, aim for 8th-grade reading level or lower (Flesch-Kincaid Grade Level ≤ 8). Government plain-language guidelines often recommend 6th-8th grade. Specialized audiences (e.g., medical professionals) may tolerate higher levels, but you should still provide summaries for patients or the public.

Do I need to simplify technical documentation?

Not necessarily. WCAG 3.1.5 recognizes that some content is inherently technical. However, you should provide supplemental explanations, glossaries, or introductory summaries that help less-experienced users understand key concepts. Consider your full audience, including new users and non-experts.

How do I measure reading level?

Use readability formulas like Flesch-Kincaid Grade Level, Gunning Fog Index, or SMOG Index. Most word processors and online tools calculate these automatically. Remember to exclude proper names and titles, and use the scores as a starting point—always validate with real users.

Can images and videos satisfy WCAG 3.1.5?

Yes. Providing visual illustrations, diagrams, or video explanations of complex text is an acceptable way to meet this criterion, as long as those alternatives are accessible (with alt text, captions, and transcripts). Multimedia can often convey information more clearly than simplified text alone.

Some TestParty features described in this article are currently under development. Visit TestParty.ai to learn more about our current capabilities and roadmap, or book a demo at TestParty.ai/book-a-demo to see TestParty in action.

Disclaimer: Some of this article was generated with Large Language Models (LLMs) and Artificial Intelligence (AI). There may be some errors and we advise you to consult with human professionals for detailed questions.