Dyslexia font tester

What makes a font dyslexia-friendly?

Readers with dyslexia often report letters that seem to crowd together, swap places or blur. Some fonts make this worse. Fonts that tend to help share a few traits:

• Sans serif. No small decorative strokes on the ends of letters.
• Letters that look clearly different. Mirror pairs like b/d and p/q, and look-alikes like I, l and 1, should be easy to tell apart.
• Round, open shapes with a generous x-height, so lowercase letters are easy to recognise.
• No italics for long passages. In an eye-tracking study, Rello and Baeza-Yates (2013) found italics slowed dyslexic readers, while Helvetica, Courier, Arial and Verdana performed well.

Spacing matters as much as the font

Crowded letters are harder to pick apart. Extra space between letters made children with dyslexia read faster and more accurately in a 2012 study in PNAS by Zorzi and colleagues. The British Dyslexia Association style guide recommends a sans serif font at 12 to 14 point or larger, letter and word spacing increased by around 30 to 35 percent, line spacing of 1.5, and a cream or soft pastel background instead of bright white.

OpenDyslexic vs Lexend

OpenDyslexic gives letters heavier bottoms so they feel anchored to the line and are harder to flip. Lexend takes a different route: clean, wide letterforms with extra spacing built in, designed to improve reading fluency.

Neither font has strong evidence that it beats a well-spaced standard sans serif. A 2017 study in Annals of Dyslexia found OpenDyslexic did not improve reading speed or accuracy for students with dyslexia. That does not make these fonts useless. Comfort affects how long you keep reading, and many readers strongly prefer one or the other. Use the tester above and trust your own experience.