Most people think of blindness as the only visual disability, but limited vision can also make access to eLearning and other online content challenging. Reduced vision may worsen with age, and it can affect anyone. This article addresses visual disabilities, which are included in the “P” of POUR (discussed in “Accessibility from the Ground Up: Build Captions and Usable Design Into All eLearning”)—content that is perceivable to learners’ senses.

“In our society, lots and lots of people wear glasses. A lot of those people, without their glasses, wouldn’t be able to function. But they don’t think of themselves as people with disabilities because glasses are ubiquitous,” said Dmitri Belser, executive director of the Center for Accessible Technology (C for AT) in Berkeley, California.

A person who is legally blind could not read 12-point type on a computer screen; neither could many adults who use reading glasses. They’d also have difficulty reading text in colors with poor contrast. About eight percent of men (and significantly fewer women) experience some form of color blindness, a reduced ability to distinguish shades of some colors, making text in some color combinations unreadable. But, as Belser points out, many learners who have visual limitations do not consider themselves “disabled.”

WCAG 2.0 guidelines include providing alternatives to text, describing non-text items, allowing learners to control the appearance—size, color, contrast—of text, and using colors that offer sufficient contrast. (Designers can use free online tools to check color contrast.) These elements of universal design are helpful to any learner who has even a mild visual limitation.

To meet WCAG Level A guidelines, eLearning designers must use visual clues other than or in addition to color to signify differences. Rather than red and green circles, for example, designers could use a green check mark and a red octagon (stop-sign shape) to signal correct and incorrect choices; they could use different colors and different line styles, such as dots and dashes, to show different subway routes or lines in a chart.

Web accessibility resources
Americans with Disabilities Act website
Dos and don’ts on designing for accessibility—Posted by Gov.UK, with links to infographics showing tips for designing for learners with a variety of accessibility needs
Section 508 Standards
WCAG 2.0 Standards

WebAIM—web accessibility consultants with a fabulous website and tons of helpful tools:

Seeing beyond color

Perception of eLearning content goes deeper than color. For people who cannot read a screen, voice recognition and screen readers are essential. These technologies, until recently both expensive and terrible according to Belser, have become mainstream: Who hasn’t encountered tools like Siri? Like captioning, these were created to accommodate disabilities but are now used to improve everyone’s user experience.

Most phones and recent-model computers have screen-reading technology built in: VoiceOver (iPhones and Macs), Narrator (Windows 10), and TalkBack (Android). Free or low-cost apps, such as NVDA (Windows) and ChromeVox (Chrome browsers), make text instantly accessible to millions of people.

But there’s more to a website than text. Learners who are blind or low-vision need an alternative to visual images. Specialized screen readers, like VoiceOver and NVDA, look beyond the obvious text on a web page. They seek out what is called “alt text”—descriptions of images that are coded into online content. But for the screen readers to read those descriptions, eLearning developers need to create them. Including alt-text descriptions is part of AA-level WCAG 2.0 compliance.

For many images, the descriptor is a simple tag—small white dog, smiling woman—but for complex diagrams you need a detailed description. Including descriptions of tables, charts, and complex images in the text provided to all learners improves everyone’s experience; linking to a text description is also an option. In videos, a separate description track complements the audio track, and all onscreen text appears in high-contrast colors. To see how this looks in practice, watch this fully accessible video that Helen Walsh, an accessible media consultant and executive director of Diverse Disability Media, created to mark the ADA’s 25th anniversary.

Most social media platforms—Twitter, for example—support alt text, Walsh says. So do many eLearning authoring tools. But most users don’t know it’s there; if they haven’t turned the feature on, they won’t be offered the option to enter alt text when creating eLearning. “Retrofitting” to add alt text later is complicated and expensive.

Navigation challenges for low-vision learners

A barrier that might not be obvious to sighted computer users is navigation: Blind and low-vision learners cannot see a cursor or pointer, making it impossible to use a mouse or trackpad. Keyboard controls that rely on color or highlighting to show cursor location are no better.

An alternative input method is essential. Screen readers and other assistive technologies usually work with a keyboard or mimic keystrokes to navigate around and between screens. Using the tab key to move from link to link, text block to text block, or page to page is common. Therefore, developers must ensure that all content is operable using a keyboard.

  • Text and headings must have accurate HTML5 coding
  • Text, particularly tables, must be formatted so that it can be read in sequential blocks
  • Tables should have summaries or text descriptions, since it can be difficult for learners to understand the context or relationships between the content of different table cells
  • Hyperlink text should convey meaning (for tips, see: Ten Ways to Create Useful Hyperlinks)

A better user experience

Many of the guidelines for accessibility add up to good, usable design.

“It’s amazing to me how many designers use pale blue text on a blue background. There are standards for what color contrast can be, but we always tell people to go beyond the standard; really make it better,” Belser said. “Yes, as a blind person, that will make it easier for me to read. But almost everyone wants it easier to read. Do you really want people to have to struggle to read your website?”

In this series

This is the third in a series of articles that discuss ways to remove different types of barriers that learners might face. Previous articles in this series:


Bigman, Alex. “Why all designers need to understand color blindness.” 99designs. 17 April 2013.

Caldwell, Ben, Michael Cooper, Loretta Guarino Reid, and Gregg Vanderheiden (eds.). “Web Content Accessibility Guidelines (WCAG) 2.0.” World Wide Web Consortium. 11 December 2008.

Hogle, Pamela. “Ten Ways to Create Useful Hyperlinks.” Learning Solutions Magazine. 6 September 2016.

Walsh, Helen. ADA 25 Celebrate PSA. YouTube video by user “ADA 25 & Beyond!” 13 April 2015.