Project overview
For ENGL 3365, I conducted a semester-long research project on which interface features improve digital readability for users with dyslexia. I evaluated reading speed (words per minute) and comprehension across multiple accessibility settings including high contrast, font choice, and adjustments to spacing.
After completing the research report, I turned the findings into a real tool: a Firefox browser extension that brings the most effective accessibility features to any website. This extension was not a class requirement, it was an applied, independent continuation of the study, built so that the research could help actual dyslexic readers in everyday contexts.
Research question & methods
My central research question was:
Which digital accessibility features most improve reading speed and comprehension for users with dyslexia?
I used SwiftRead to create six reading conditions, one control and five accessibility-focused variants, testing features frequently cited in dyslexia research: high contrast, letter spacing, paragraph spacing, line spacing, and the OpenDyslexic font. Participants (both dyslexic and non-dyslexic) completed each test, followed by comprehension questions.
Key findings
Some features improved readability dramatically; others had mixed or unexpected effects.
- High contrast mode significantly increased speed and comprehension for both groups.
- Paragraph spacing produced some of the largest speed gains while maintaining comprehension.
- Letter & word spacing improved legibility for dyslexic readers and accelerated reading for everyone.
- Line spacing unexpectedly decreased comprehension for dyslexic readers.
- OpenDyslexic produced near-perfect comprehension scores and major WPM increases.
The conclusion was clear: a combination of OpenDyslexic, high contrast mode, and spacing adjustments provides the strongest overall improvement for dyslexic readers.
From research paper to browser extension
Once the study was complete, I wanted the findings to have life beyond the assignment. My girlfriend, who has dyslexia, often struggled to read long assignments on platforms like Canvas and Blackboard. That context motivated me to build a tool that applied the research to real-world reading environments.
I began with a simple prototype that injected the OpenDyslexic font into web pages. After testing it with dyslexic readers (the same audience from my study), I expanded the extension to include the three most effective features from the research:
- OpenDyslexic font toggle
- High contrast mode
- Adjustable letter and paragraph spacing
Their feedback also shaped the UI: readers asked for sliders instead of preset spacing options, and for the extension’s own interface to use the same accessible font it applied to webpages.
Implementation
The extension uses the Firefox WebExtensions API. When opened, it injects CSS into the active tab that:
- switches text to OpenDyslexic where possible,
- adjusts spacing with
letter-spacing,word-spacing, and paragraph margins, - and applies a high contrast palette that meets WCAG contrast ratios.
All settings are stored locally, and the extension performs no analytics, tracking, or data collection, mirroring dyslexia research that emphasizes reducing cognitive load, distraction, and unnecessary interface noise.
Outcomes
The extension gives dyslexic readers access to evidence-based reading support anywhere on the web. Friends and classmates with dyslexia now use it to improve readability on LMS platforms, news sites, and long-form articles. Publishing it on Firefox Add-ons makes these tools accessible to a wider audience beyond the classroom.
What I learned
This project taught me how empirical research can directly inform accessible interface design. It also strengthened a belief that runs through my work: when we design with disabled users in mind, we often make interfaces better for everyone.
Explore the research and the tool that came from it: