Canvas - Comparing Canvas Accessibility Checkers [UW-Madison]

This document explains which accessibility checkers are available in Canvas, and the items each one can scan.

   

Which accessibility tools are available in Canvas?

There are two accessibility tools available in Canvas at UW-Madison:

  • UDOIT
  • Canvas Accessibility Checker in the Rich Content Editor (RCE)

UDOIT

The UDOIT Accessibility Checker expands accessibility checks beyond the text added via the rich text editor, and also includes files uploaded to Canvas courses. UDOIT Advantage allows you to: 

  • Rapidly scan PDF and Word files in a course to detect potential accessibility issues such as scanned or untagged PDFs or outdated Word document formats.

  • View, sort, and filter all files in a course by content type, accessibility issue or other filters.

  • Auto-generate alternate formats of a file including web page (HTML), Audio File (MP3), ePUB Digital Book, Plain Text, and Auto Tagged PDF.

  • Take actions to remediate a course file to improve accessibility such as replacing the file with a UDOIT-generated Canvas page, uploading a more accessible file, or deleting the file from the course – all within the UDOIT interface.

For more information, please see UDOIT - Getting Started [UW-Madison]

Canvas Accessibility Checker in the Rich Content Editor (RCE)

The Rich Content Editor includes an accessibility tool that detects common accessibility errors within the editor. You can use the Accessibility Checker to design course content while considering accessibility attributes. This tool only verifies content created within the Rich Content Editor. You may use other accessibility tools to verify additional content in Canvas

Instructure recently announced a new accessibility checker called the Canvas Course Accessibility Checker. At a future date, Learn@UW will announce more details about this checker, including the timeline for its availability at UW-Madison.UDOIT - Getting Started [UW-Madison]

What areas of a course can each one scan?

The Canvas Accessibility Checker in the Rich Content Editor (RCE)

This checker will only check content currently being edited in the Rich Content Editor.

UDOIT

Highlights barriers in the following areas of a course:

  • Announcements
  • Assignments
  • Classic Quiz Instructions
  • Discussions
  • Pages
  • Syllabus
  • Module URLs
  • Files (Excel, PDF, PowerPoint, Word)
Important: Scope of Scan vs. Comprehensive Accessibility

To ensure the accurate framing of our accessibility efforts, sponsors should be aware of the specific content types that UDOIT does not or only partially scans.

  • Limited Scope for Quizzes: UDOIT currently does not scan classic quiz questions or question banks. It only scans the quiz description field. It also does not scan New Quizzes at this time. Course content stored exclusively in these formats is not factored into the accessibility score.
  • Limited Document Scanning: While UDOIT scans uploaded files (PDFs, Word, PPT, Excel), the checks are often focused on basic structural integrity and file format issues (e.g., looking for scanned, image-only PDFs, or outdated XLS formats). It does not perform a comprehensive, deep structural check of document accessibility. For example, an Excel file may pass UDOIT's check if it is in the correct format, but still be highly inaccessible due to complex, untagged, or merged cells.
  • Canvas Rich Content Editor does not scan files. To see what UDOIT scans for and in what supported files, please see the files section of UDOIT User Guide.
  • Need for Manual Review: Because a 100% score is only 100% compliance on the content and file properties UDOIT scans, course content heavily reliant on complex files (e.g., data-heavy PDFs, detailed spreadsheets) requires dedicated manual review to achieve true compliance.

What items are flagged in each checker?

Links

Both Canvas Accessibility Checker (RCE) and UDOIT detect:

  • Adjacent links do not have separators / Adjacent Links Found

UDOIT

  • Linked Image Does Not Have a Descriptive Alternative Text
  • Link Has Nondescript Text
  • Link Does Not Contain Text

Image Alternate Text

Both Canvas Accessibility Checker (RCE) and UDOIT detect:

  • Non-decorative images are missing alternate text 
  • Images alternate text is the filename 
  • Images alternate text is too long (120 character limit is set to align with the Accessibility Checker in the Canvas Rich Content Editor)

Only UDOIT Detects: 

  • Alternative Text Appears To Be a Generic Placeholder
  • Input Image May Be Missing an "Alt" Attribute
  • Image Description Is Identical to Alt Text
  • Decorative Image Does Not Have an Empty Alternative Text

Audio/Video

The Canvas Accessibility Checker (RCE)

  • Does not scan Audio/Video

UDOIT

  • Embedded Video Is Missing Captions
  • Multimedia Object is Missing Text Equivalent
  • Embedded Content May Be Inaccessible on Mobile Devices
  • Multimedia Object May Not Be Accessible
  • Links to Multimedia Require Transcripts
  • Links to Sound Files Require Transcripts
  • Video Captions Appear to Be Automatically Generated And May Contain Errors
  • Video Captions Are Missing
  • Captions Are In a Language Different From The Course Default

Headings

Both The Canvas Accessibility Checker (RCE) and UDOIT

  • Headings are not sequential / Heading Levels Have Been Skipped

The Canvas Accessibility Checker (RCE)

  • Heading length is greater than 120 characters

UDOIT 

  • One or More Heading Elements Do Not Contain Text
  • Headings May Be Missing
  • Styles Might Be Used Instead of Semantic Markup For Structure

Tables

Both The Canvas Accessibility Checker (RCE) and UDOIT

  • Table is missing heading cells/Table Does Not Include Header Rows or Columns
  • Table headings are missing scope / Table Headers Are Missing Row or Column Scope Attributes

Only The Canvas Accessibility Checker (RCE)

  • Table is missing captions 

UDOIT 

  • Styles Might Be Used For Tabular Data Where Semantic Markup May Be More Appropriate
  • Table Without Content Detected

Color and Design

The Canvas Accessibility Checker (RCE)

  • Color contrast is not adequate 

UDOIT

  • Insufficient Text Color Contrast With the Background
  • Potential Use of Color Alone to Communicate Information

Miscellaneous

The Canvas Accessibility Checker (RCE)

  • Lists are not properly marked in HTML 

UDOIT

  • Content May Exceed Recommended Length For Readability (3000+ words) 
  • Deprecated Base Font Tag in Use
  • Deprecated Blink Tag in Use
  • Deprecated Font Tag in Use
  • Marquee Tag Causes Readability Issues
  • Document Reading Direction Not Found 


Keywords:
udoit you do it doit rce rich content editor course compliance scanner accessible legislation flagging 
Doc ID:
158672
Owned by:
Learn@UW Madison in Learn@UW
Created:
2026-02-17
Updated:
2026-02-24
Sites:
DoIT Help Desk, Learn@UW