Fonts and Font Sizes

Font choice and size are important accessibility considerations.

Choose Easy-to-Read Fonts

Fonts should be clear and legible, though there's no consensus on what constitutes the most accessible font. Different sources provide a range of recommendations:

• Siteimprove: Tahoma, Calibri, Helvetica, Arial, Verdana, Times New Roman
• ReciteMe: Arial, Calibri, Century Gothic, Helvetica, Tahoma, Verdana
• Penn State: Verdana, Lucida Sans/Grande, Tahoma, Georgia, Palatino variants, Andika

The Stanford Identify Guide's official fonts—Source Sans Pro, Source Serif Pro, and Roboto—are excellent accessible choices that also ensure brand compliance.

Avoid very light font weights, especially at smaller sizes. Use regular weight for body text and reserve lightweight and bold for emphasis.

For more information, see Gareth Ford Williams' article: A Guide to Understanding What Makes a Typeface Accessible.

Special Note for Web

Users can change fonts on the web. While specialized fonts like OpenDyslexic exist for dyslexia, preferences vary widely. Don't prevent font changes (e.g., avoid using !important on font declarations in CSS).

Select an Appropriate Font Size

Minimum recommended font sizes:

• Word, PDF, and documents: 12pt
• PowerPoint: 18px (online), 24px (in-person)
• Web: 16px (approximately 12pt on screen)

Special Note for Web

Use relative sizing rather than fixed sizes. See Website Resizing Techniques for details.

Consider Line Length

Optimal line length is 50–120 characters. Lines that are too short feel choppy; lines that are too long require excessive eye movement.

For documents, 12pt text with standard margins typically achieves appropriate line length. For responsive web design, aim for this range at standard window sizes, understanding that length will vary across devices.