Serif fonts have small decorative lines (called serifs) at the ends of letter strokes. While these fonts work well in print, they can create extra visual noise in digital interfaces that makes text harder to read. For people with dyslexia, these additional details can make letters appear to blur or run together, increasing reading difficulty.

Sans-serif fonts like Arial, Open Sans, or Inter provide cleaner letter shapes that are easier to distinguish. Their simpler forms reduce cognitive load and improve letter recognition, especially at smaller sizes. Many dyslexia-friendly fonts like OpenDyslexic are specifically designed with letter shapes to prevent common reading errors like letter flipping or mixing.