When designing for accessibility, what are the best practices for choosing fonts that ensure readability for users with visual impairments?

Designing for accessibility involves selecting fonts that enhance readability for users with visual impairments. Here are the best practices:

1. Prioritize Legibility

Sans-serif Fonts: Use clean, simple sans-serif fonts like Arial, Verdana, or Tahoma, which are easier to read at smaller sizes.

Avoid Decorative Fonts: Minimize use of overly stylized or script fonts, especially for body text.

2. Choose Appropriate Text Sizes

Use a font size of at least 16px for body text. Allow users to scale text without loss of readability.

Avoid text that’s too small or compressed.

3. Maintain Adequate Contrast

Ensure strong contrast between text and background (e.g., black on white or yellow on black).

Follow WCAG 2.1 guidelines for contrast ratios:

4.5:1 for normal text.

3:1 for large text (18px+ or 14px bold).

4. Use Distinct Letterforms

Opt for fonts with clear differentiation between similar characters (e.g., l, I, 1 or O, 0).

Avoid condensed fonts that can make letters harder to distinguish.

5. Limit Line Length and Spacing

Line Length: Keep text lines between 45–75 characters for optimal readability.

Line Spacing: Use 1.5x to 2x line height to avoid cramped text.

6. Avoid All Caps for Long Text

Uppercase text is harder to read for extended content. Use mixed case for improved readability.

7. Consider Dyslexia-Friendly Fonts

Use fonts like OpenDyslexic, Dyslexie, or others designed to reduce confusion for dyslexic readers.

Alternatively, fonts with consistent letterforms and ample spacing work well.

8. Test Readability with Real Users

Conduct usability testing with individuals who have visual impairments to ensure fonts meet their needs.