What is it?

Legibility is the term that describes how easily you can make out each individual letter or number and tell them apart.

Readability describes how easily your brain can interpret letters into words with meaning.

Understandability describes whether or not the information that people are seeking is clear, can they find it, do they know how to use it and whether it is it appropriate for the intended audience.

Impact

Following the accessibility principles of legibility, readability, and understandability ensures that content can be effectively perceived, processed, and used by the widest range of learners, including those with visual, cognitive, or linguistic differences. Legibility focuses on the visual clarity of text, such as font choice, contrast, and spacing, so that characters and words are easily distinguishable. Readability addresses the structure and complexity of the language, making sure that vocabulary, sentence length, and formatting support comprehension rather than hindering it. Understandability extends beyond language to include logical organization, predictable navigation, and clear instructions, allowing students to not only read the text but also grasp its meaning and act on it. Taken together, these principles foster equitable access, reduce cognitive load, and make information more inclusive and effective for diverse audiences.

Dos and Don'ts

• Do use simple fonts with distinguishable characters.
  • Don't assume there is a single best font.
  • Do use fonts such as Roboto, Poppins, Verdana, Calibri, Georgia, Palatino, Garamond, Book Antiqua, Baskerville, and Times New Roman.
• Do limit the number of fonts used in one document.
• Don't use excessive bold, italics, or all caps.
• Do left align blocks of text.
• Don't fully justify blocks of text.
• Do use 1.5 line spacing.
• Don't use smaller than 12 point type.
• Do limit line lengths to between 60 and 75 characters per line.
• Do provide clear, complete directions for all tasks.
• Do use plain language.
• Do write for appropriate audience and reading level.
• Don't use acronyms, abbreviations, and subject-specific jargon except where necessary.

How-To

• CAT Resource: Legible & Readable Text
• Plain Language Association International: What is plain language?
• Hemingway Readability Checker

Need More Help?

You can always book a one-on-one consultation, visit one of our ed tech labs, or email cat@temple.edu for additional assistance!