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How to present more readable text for people with dyslexia


The presentation of a text has a significant effect on the reading speed of people with dyslexia. This paper presents a set of recommendations to customize texts on a computer screen in a more accessible way for this target group. This set is based on an eye tracking study with 92 people, 46 with dyslexia and 46 as control group, where the reading performance of the participants was measured . The following parameters were studied: color combinations for the font and the screen background, font size, column width as well as character, line and paragraph spacings. It was found that larger text and larger character spacings lead the participants with and without dyslexia to read significantly faster . The study is complemented with questionnaires to obtain the participants’ preferences for each of these parameters, finding other significant effects. These results provide evidence that people with dyslexia may benefit from specific text presentation parameters that make text on a screen more readable. So far, these recommendations based on eye tracking data are the most complete for people with dyslexia.

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    Words with no consistent correspondence between grapheme and phoneme, e.g., vase pronounced as /vāz/.

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    A nonword is a word that has no meaning, is not known to exist, or is disapproved.

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    The CYMK code for the colors and their contrast are shown in “Appendix 1.”

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    The fonts tested were: Arial, Arial Italic, Computer Modern Unicode, Courier, Garamond, Helvetica, Myriad, OpenDyslexic, OpenDyslexic Italic, Times, Times Italic and Verdana [79].

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The authors would like to thank Mari-Carmen Marcos for her assistance with the eye tracking hardware. Special thanks are due to the participants with dyslexia and their families.

Author information



Corresponding author

Correspondence to Luz Rello.

Additional information

This research was conducted while Luz Rello was doing her PhD at Web Research Group, Universitat Pompeu Fabra, Barcelona.


Appendix 1: color and brightness

The CYMK/RGB codes for the contrast and colors used are:

Text contrast:

  • 0 % (pure black font, 000000/0,0,0): brightness text: 255; brightness background: 0; brightness difference: -255; color difference: 765.

  • 25 % (404040/64,64,64): brightness text: 255; brightness background: 63; brightness difference: 192; color difference: 573.

  • 50 % (7E7E7E/126,126,126): brightness text: 255; brightness background: 126; brightness difference: 129; color difference: 387.

  • 75 % (BFBFBF/191,191,191): brightness text: 255; brightness background: 191; brightness difference: 64; color difference: 191.

Background contrast:

  • 100 % (pure black background, 000000/0,0,0): brightness text: 0; brightness background: 255; brightness difference: -255; color difference: 765.

  • 25 % (404040/64,64,64): brightness text: 63; brightness background: 255; brightness difference: -192; color difference: 573.

  • 50 % (7E7E7E/126,126,126): brightness text: 126; brightness background: 255; brightness difference: -129; color difference: 387.

  • 75 % (BFBFBF/191,191,191): brightness text: 191; brightness background: 255; brightness difference: -64; color difference: 191.


  • black (000000/0,0,0)/white (FFFFFF/255,255,255):

    Color difference: 765, brightness difference: 255;

  • off-black (0A0A0A/10,10,10)/off-white(FFFFE5/255,255,259):

    Color difference: 735, brightness difference: 245;

  • black (000000/0,0,0)/yellow (FFFF00/255,255,0):

    Color difference: 510, brightness difference: 226;

  • blue (00007D/0,0,125)/white (FFFFFF/255,255,255):

    Color difference: 640, brightness difference: 241;

  • dark brown (1E1E00/30,30,0)/light mucky green (B9B900/185,185,0):

    Color difference: 310, brightness difference: 137

  • brown (282800/40,40,0)/mucky green (A0A000/160,160,0):

    Color difference: 240, brightness difference: 107

  • black (000000/0,0,0)/creme (FAFAC8/250,250,200):

    Color difference: 700, brightness difference: 244;

  • blue (00007D/0,0,125)/yellow (FFFF00/255,255,0):

    Color difference: 635, brightness difference: 212

Appendix 2: text example

¿Soy dix-leso?

by Marcela Paz (Papelucho series)

Por la tarde fuimos al doctor. Era un señor bastante preguntón, que se hacía el simpático por fuera, pero se notaba que era malo por dentro. Me martilló las costras y otras cuestiones con un martillito lindo. Y mientras hablaba y hablaba con la mamá se martillaba su otra mano gorda.

Yo pensaba qué pasaría si en vez de su mano gorda se martillara el tremendo grano que tenía en la nariz? Pero apenas se lo rascó y siguió dale que dale hablando de “este niño”. Y “este niño” por aquí y “este niño” por allá.

Traté de entender lo que decían.

Casi lo entendí. No estoy seguro si la cosa es que soy superdotado o viceversa. Menos mal que además parece que soy dix-leso, que es algo muy guay y como distinto. Y tampoco me importa mucho ser así.

Mis padres fueron al colegio a hablar con mi profe y volvieron furiosos.

De todos modos yo tengo mi enfermedad propia y nadie me la quita.

Pero en la noche, me desvelé. Porque claro, en el día a uno le gusta ser enfermo y en la noche no. Así que desperté a mi padre apretetándole la nariz porque es el único modo de despertarlo.

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Rello, L., Baeza-Yates, R. How to present more readable text for people with dyslexia. Univ Access Inf Soc 16, 29–49 (2017).

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  • Dyslexia
  • Eye tracking
  • Textual accessibility
  • Text customization
  • Recommendations
  • Readability
  • Text color
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