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19 November 2012]

WAI R&D Symposia » Text Customization Home » Proceedings » This paper.

This paper is a contribution to the Text Customization for Readability Online Symposium. It was not developed by the W3C Web Accessibility Initiative (WAI) and does not necessarily represent the consensus view of W3C staff, participants, or members.

When One Size Fits One — A Position Paper on Achieving Readability for People with Low Vision Through Web Text Customization


This position paper outlines issues and opportunities for achieving readability for people with low vision through web text customization. Flexible text customization functionality is essential for ensuring equal access to the Web for many users, and I commend the W3C WAI RDWG for exploring its benefits. As a disability advocate, businesswoman and consumer with low vision, I offer this user-centered perspective. Text customization is not a one size fits all proposition. Text customized for one person may be unreadable for another. Even for an individual, optimal customization may vary as vision fluctuates. Web guidelines and practices must provide highly flexible solutions that meet the "one size fits one" requirements of users with low vision. I share my observations, personal experiences as a low vision web user, and recommendations to improve readability through web text customization.

Problem Description

Many types of web users may benefit from more text customization. This paper focuses on users with moderate and severe low vision. Consider the numbers. The World Health Organization estimates that 39 million people in the world are blind, and another 246 million people have low vision. Ninety percent of these people live in developing countries. (WHO 2012) Therefore, low vision web users may outnumber blind web users by more than 6.3 to 1. Improvements in web text customization will increase accessibility for millions.

As a lay person, I cannot evaluate whether the difficulties with web text readability are due to insufficient standards and guidelines, lack of web standards implementation, ineffective web testing practices, inadequate testing tools, and/or poor user training. I suspect each may have a role. I am convinced that this problem stems from a lack of understanding of the needs of low vision users, as well as insufficient training on strategies for ensuring access through readability.

From my perspective, even though low vision web users far outnumber blind users, low vision readability receives less attention than non-visual accessibility. Why this disparity?

One cause is lack of awareness. As I participate in web accessibility symposiums and trainings, I observe a lack of awareness about the needs of users with moderate and severe low vision. I have met web experts and testers who equate full web accessibility with nonvisual accessibility. Others believe text customization for readability is already provided through browsers with zoom features or magnification software. Some suggest that the color use and color contrast provisions in existing guidelines suffice. Few realize WCAG 2.0 contrast guidelines address only the needs of users with near normal vision, acuities of 20/40 and 20/60. Users with less vision are expected to use assistive technologies.

Another contributor to the awareness deficit is insufficient self-advocacy by users with low vision who lack the resources and forum to express their web text customization needs. They cannot easily influence industry leaders and policy makers to implement improvements. Consequently, millions of low vision web users remain isolated and frustrated, destined to suffer silently while unintentional barriers persist and new barriers are erected.

One Size Fits One — My Web Text Customization Experiences

I wish every website developer could spend a day with a low vision user like me. My lifelong visual disability impairs my perception of colors, contrast sensitivity, and ability to read. My visual acuity fluctuates daily between 20/100 and 20/400. I am very photophobic so light backgrounds on webpages hurt my eyes and make reading impossible.

Screen magnifiers do not help. They cannot customize text to optimize my reading comfort, speed and endurance. Products like Zoomtext and Magic enlarge all elements on a webpage equally and waste valuable screen real estate. Users can only read a portion of a page at a time. They do not reflow text so users must scroll between screens to read a single line. Text is jumpy and tiresome on the eyes. Under inverse settings, customizing colors is basically a guessing game.

On my iPad I invert Colors and use Zoom. I also increase the default font size to very large. At the office I use an HP Touch Smart computer which has a 24" screen. I run Office 2010, Windows 7, and Internet Explorer 8. In settings, I reduce screen resolution by 25%, increase DPI to 200%, and activate the Windows High Contrast Black scheme and extra-large mouse pointer.

While I can use a screen reader, I prefer reading the Web visually. I enjoy the variety in web design. In terms of text customization on the Web, I read best when text is large and bright, while backgrounds are dark. Global Inverse contrast and reverse color schemes are indiscriminant, changing backgrounds which are already dark to white or converting text boxes to white on white or black on black, which are unreadable. They invert photographs making them indecipherable as well.

Since websites use a variety of font sizes, styles, and color combinations, I may require different text customization treatments within a single site. And web-based PDF documents are often inaccessible. Surprisingly, my totally blind husband is able to successfully use his screen reader on webpages that are completely unreadable by me.

Reading some web text requires me to copy it into Word, increase font size, adjust colors, and increase margins to insure that text reflows properly. These text gymnastics are tedious and time consuming. Usually, I walk away from my PC frustrated, discouraged, and completely fatigued. On good days, once text is properly customized, I can transfer it to my iPad, cuddle up with my son, and read him a story easily.


To improve readability and flexibility for low vision web users, I recommend the following:

  • Build text customization functionality directly into websites and mainstream products including browsers and operating systems, rather than relying on assistive technology. Small Assistive Technology companies that sell screen magnification cannot meet the needs of many low vision users. We must not depend on such companies to ensure worldwide web access since their products are unaffordable and inaccessible to most people with low vision. (footnote: see AFB Access World, October 2012)

  • Employ testers with real life experiences in low vision to validate web text customization and accessibility. This should include testers with varying skill levels and testers with a variety of visual disabilities. It is important not to rely solely on testers that use screen readers.

  • Best Practices in website testing should include evaluating the readability of the site using Windows' high contrast and high contrast black schemes as well as the Apple iOS Invert Colors setting.

  • Build awareness through increased training for policymakers, developers, and content generators. Compelling case studies including photographs would crystalize understanding and motivate improvements.

  • Empower Users with low vision through Training. After interviewing professionals with low vision, I found that many do not use the current workarounds like the Zoom slider bar in Internet Explorer. User friendly training on YouTube might help.

  • Require that all PDF's posted on the web be completely customizable to meet individual reading needs.


The challenge of achieving true text customization cannot be overestimated. Even when standards for best practices for e- text customization are established, they must be disseminated and promoted to insure broad acceptance. Implementation will require new Text Customization Accessibility guidelines, as well as appropriate government regulations. Each must echo the requirements that all e-text must be customizable. With text customization, one size does not fit all, rather "one size fits one". Text customization guidelines must leverage the power of technology to deliver the optimal web reading experience for people with low vision.


World Health Organization. (2012). Visual impairment and blindness. WHO Fact Sheet N°282, June 2012. Available: http://www.who.int/mediacentre/factsheets/fs282/en. Last accessed 14 September 2012