Why Your LMS Accessibility Checker Is Not Enough

Canvas has the Accessibility Checker. Blackboard has Ally. Brightspace has its accessibility tools. If your LMS already has a built-in checker, you might wonder whether you need anything else.

The short answer: yes, you do. Built-in LMS accessibility checkers are useful but limited. Understanding what they catch and what they miss is critical for any institution working toward genuine WCAG 2.1 AA compliance.

What Built-In Checkers Do Well

LMS accessibility checkers are designed for the content created inside the LMS — HTML pages, discussion posts, announcements, and assignment descriptions. For this content, they typically catch:

• Missing alt text on images
• Empty heading tags
• Broken heading hierarchy (jumping from H1 to H3)
• Low color contrast in text
• Missing table headers
• Links with generic text like "click here"

These are real issues, and catching them at the point of creation is valuable. When a faculty member creates a Canvas page and sees an accessibility warning immediately, that is a teachable moment.

What Built-In Checkers Miss

The limitation is scope. LMS checkers only analyze content created inside the LMS itself. They cannot analyze:

Uploaded Documents

The majority of course content in most universities is not created in the LMS. It is created in Word, PowerPoint, Excel, or LaTeX and then uploaded as files. A PDF with no heading structure, no alt text, and no reading order will upload to Canvas without any warning. The LMS checker never sees inside that file.

PDF Structure

PDF accessibility is a specialized problem. A PDF needs tagged structure (headings, paragraphs, lists, tables), a defined reading order, alternative text for images, and proper language metadata. None of the major LMS platforms perform this level of analysis on uploaded PDFs.

Video and Audio

While some LMS platforms integrate with captioning services, the built-in checker typically does not verify caption quality, accuracy, or synchronization. Auto-generated captions are notorious for errors in technical and discipline-specific vocabulary — exactly the kind of content universities produce.

Scanned Documents

A scanned PDF is essentially an image of text. Without OCR processing, it contains zero accessible content. LMS checkers do not perform OCR or flag scanned documents as inaccessible.

Complex Data Tables

Excel spreadsheets with merged cells, multi-level headers, and color-coded data present accessibility challenges that go far beyond what any LMS checker evaluates.

The Coverage Gap

Research from the WebAIM Million study and similar analyses consistently shows that automated tools catch approximately 30 to 40 percent of WCAG violations. LMS-specific checkers are even more limited because they only analyze one content type.

When you consider that:

• 30 to 40 percent of issues are detectable by any automated tool
• LMS checkers only scan content created in the LMS
• Uploaded documents represent the majority of course content

The actual coverage of an LMS-only approach is often below 15 percent of total accessibility issues in a course.

A Layered Approach

The most effective accessibility strategy uses multiple tools at different levels:

1. LMS checker for content created in the LMS (keep using it — it is still useful)
2. Document scanner for uploaded files (PDFs, PowerPoints, Word docs, Excel, LaTeX)
3. Video captioning with human review for accuracy
4. Web scanner for the university website and web applications
5. Manual review for complex content that automated tools cannot fully evaluate

Each layer catches issues that the others miss. No single tool — including Aelira — catches everything. But a layered approach with automation at each level gets you dramatically closer to compliance than relying on a single built-in checker.

What to Look For

When evaluating accessibility tools to complement your LMS checker, consider:

• Does it scan the file formats your faculty actually use?
• Can it integrate with your LMS so faculty do not need to leave their workflow?
• Does it provide remediation, not just scanning?
• Can it handle the volume of documents your institution produces?
• Does it provide audit trails for compliance reporting?

The goal is not to replace your LMS checker — it is to fill the gaps it was never designed to cover.