Walk into any conversation about reading accommodations and someone will mention OpenDyslexic. The font, with its heavy-bottomed letterforms designed to prevent visual letter-flipping, has become one of the most recognized accessibility tools in education. Chrome extensions that switch page fonts to OpenDyslexic have millions of installs. Teachers recommend it. IEPs sometimes reference it by name.
But does it actually help? The research is more complicated than the marketing suggests, and the answer matters for how schools allocate their accommodation resources.
The Fonts
Several typefaces have been designed or adopted specifically for readers with dyslexia. Here are the most common ones you will encounter in schools.
OpenDyslexic
Created by Abelardo Gonzalez in 2011, OpenDyslexic is a free, open-source typeface designed with weighted bottoms on each letter. The theory is that the heavier bottom half provides a visual anchor, making it harder for letters to appear to rotate or flip in the reader's perception. The letters b, d, p, and q, which are common sources of confusion for dyslexic readers, have distinct shapes rather than being mirror images of each other.
OpenDyslexic is the most widely available dyslexia font. It is built into Chromebook accessibility settings, available as a Chrome extension, and supported by apps like Kindle and Google Play Books.
Lexie Readable (formerly Lexia Readable)
Designed by Keith Bates at K-Type, Lexie Readable takes a different approach. Rather than adding weighted bottoms, it focuses on making each letter as distinct as possible through varied shapes. It is based on Comic Sans but refined for better readability at smaller sizes and in body text. The lowercase a is single-story (like handwriting) rather than double-story (like most printed fonts), which some argue is more natural for struggling readers.
Comic Sans
Yes, Comic Sans. The font that designers love to mock has a genuine following in special education. Like Lexie Readable, it uses simple, distinct letterforms. The letters are less uniform than in traditional typefaces like Times New Roman, which can actually help readers with dyslexia distinguish between similar-looking characters. Several studies have specifically tested Comic Sans against serif fonts and found that some dyslexic readers prefer it and read slightly faster with it.
Dyslexie
Created by Dutch designer Christian Boer, who has dyslexia himself, Dyslexie uses variations in line thickness, slightly tilted letters, and larger openings in letters like c and e to increase distinguishability. Unlike OpenDyslexic, Dyslexie is a commercial font and requires a license for institutional use.
Atkinson Hyperlegible
Designed by the Braille Institute, Atkinson Hyperlegible is not specifically marketed for dyslexia but was designed for maximum legibility for low-vision readers. It focuses on distinguishing similar letterforms (I, l, 1; O, 0; rn vs m). It has gained traction in accessibility communities as a well-designed, legible alternative that does not have the stigma some students feel with obviously "special" fonts.
What the Research Says
Here is where the conversation gets difficult. The research on dyslexia-specific fonts is mixed at best, and some of it directly contradicts the claims made by font creators and advocates.
Studies Showing Modest Benefits
Rello and Baeza-Yates (2013) conducted an eye-tracking study with 48 dyslexic readers and found that OpenDyslexic did not significantly improve reading speed or accuracy compared to standard fonts. However, participants showed a subjective preference for OpenDyslexic. A subset of participants showed slightly longer fixation times with OpenDyslexic, which the researchers interpreted as more careful reading rather than more difficult reading.
Wery and Diliberto (2017) tested OpenDyslexic with 24 students diagnosed with dyslexia across grades 2 through 5. They found no statistically significant improvement in reading rate or accuracy with OpenDyslexic compared to Arial and Times New Roman.
Studies Showing No Benefit
Kuster and colleagues (2018) conducted what is considered one of the most rigorous studies, testing 170 Dutch children with dyslexia. They found no significant effect of dyslexia-specific fonts on reading speed, reading accuracy, or word recognition. Their conclusion was direct: "There is no evidence that these fonts provide benefits for reading."
Marinus and colleagues (2016) tested a large sample of children with and without dyslexia and found no significant benefit of dyslexia-specific fonts for any group.
What the Studies Agree On
Across the literature, a few consistent findings emerge:
- No font has been shown to reliably improve reading accuracy (number of errors) for dyslexic readers in controlled studies.
- Reading speed differences, when found, are small and often not statistically significant.
- Students often express a preference for dyslexia-friendly fonts, even when objective performance measures do not improve.
- Sans-serif fonts in general (Arial, Verdana, Calibri) tend to be slightly more readable than serif fonts (Times New Roman, Georgia) for struggling readers, regardless of whether the font is "dyslexia-specific."
- Font size and spacing matter more than font face. Increasing font size to 14-16pt and adding extra letter spacing and line spacing produces more consistent reading improvements than switching to a specialty font.
Why Preference Still Matters
The lack of strong empirical evidence does not mean schools should dismiss dyslexia-friendly fonts entirely. Here is why.
Anxiety reduction. Reading is an emotionally loaded activity for students with dyslexia. Many of these students experience significant anxiety when faced with reading tasks. If switching to OpenDyslexic makes a student feel more confident or less anxious about reading, that psychological benefit is real even if the font itself is not measurably improving decoding.
Sense of control. Giving students the ability to choose their font (and font size, and page colors) gives them a sense of agency over their reading experience. This sense of control is associated with increased motivation and task persistence in learning research.
Low cost, no downside. Unlike some accommodations that require significant time, money, or staffing, offering a font choice is essentially free. If a student wants to use OpenDyslexic and it does not harm their reading performance, there is no reason to refuse.
Individual variation. The studies cited above report group averages. Some individual students may genuinely benefit from these fonts even if the average effect across a sample is near zero. Dyslexia is heterogeneous; what helps one student may not help another.
How to Make Dyslexia Fonts Available on School Devices
On Chromebooks (built-in)
Chrome OS includes OpenDyslexic in its accessibility settings:
- Open Settings > Accessibility > Appearance.
- Under Font, students can select OpenDyslexic.
- This changes the Chrome browser's default font but does not affect content within web pages, which use their own CSS-specified fonts.
To change fonts within web page content, you need a Chrome extension that overrides page styles. ReadingVox includes a font selector tool that applies the chosen font (including OpenDyslexic) to all page content and the reading panel without requiring a separate extension.
System-wide font installation
If you want OpenDyslexic available in Google Docs, Slides, and other applications:
- Download OpenDyslexic from opendyslexic.org.
- For Chromebooks, system fonts cannot be easily installed at scale. Use a web-based font override extension instead.
- For Windows or Mac devices, deploy the font via your MDM (Mobile Device Management) solution or group policy.
Accommodations with Stronger Evidence
While offering font choices is a reasonable low-cost accommodation, schools should prioritize interventions that have stronger research support.
Text-to-speech with word highlighting. Dual-coding (hearing words while seeing them highlighted) has substantially more research support than font changes. TTS helps with both decoding and comprehension simultaneously.
Increased font size and spacing. Zorzi and colleagues (2012) published a well-cited study in the Proceedings of the National Academy of Sciences showing that extra-large letter spacing significantly improved reading accuracy and speed in children with dyslexia. The effect was larger than any font-change study has shown.
Structured literacy instruction. Orton-Gillingham and similar structured, explicit, multisensory reading instruction approaches have the strongest evidence base for improving reading outcomes in dyslexic students. These are instructional approaches, not technology tools, but they should be the foundation of any dyslexia support program.
Extended time. Giving students extra time on reading tasks and assessments is one of the simplest and most effective accommodations, allowing students to decode at their own pace without time pressure.
Reduced visual clutter. Screen masks and line guides that isolate one or two lines of text at a time help students who experience visual crowding, where surrounding text interferes with the perception of the target word. This accommodation has more research support than font changes.
A Balanced Approach
The practical recommendation for schools is this: make dyslexia-friendly fonts available as a student choice, but do not rely on them as a primary accommodation. Include them as part of a broader toolkit that prioritizes text-to-speech, adjustable spacing and sizing, visual focus tools like screen masks, and structured reading instruction.
ReadingVox includes OpenDyslexic in its built-in font selector alongside Atkinson Hyperlegible, system sans-serif, and system serif options. Students can switch fonts with one click and combine the font change with other accommodations like TTS, the screen mask, and page themes. This approach gives students the autonomy to customize their reading experience while ensuring they also have access to the tools with stronger evidence behind them.
The best accommodation is the one the student will actually use. If that includes OpenDyslexic, great. Just make sure it is not the only thing you offer.