Accessible Font Size Checker

Ensure your typography meets accessibility standards with our interactive font size checker. Test readability across different devices and validate WCAG compliance in real-time.

100%
100%
1.5
0.00em
0.00em
The quick brown fox jumps over the lazy dog

WCAG Compliance Check

Resizable to 200%✓
Adequate Spacing✗
Minimum Size✓

Generated CSS

.your-text {
  font-size: 16px;
  line-height: 1.5;
  letter-spacing: 0em;
  word-spacing: 0em;
}

Understanding Font Size Accessibility

Font size accessibility is crucial for ensuring your content is readable by all users, regardless of their visual abilities or viewing conditions. The Web Content Accessibility Guidelines (WCAG) provide specific recommendations for text size and scaling.

Key WCAG Requirements

  • Text must be resizable up to 200% without loss of functionality
  • Text spacing must be adjustable without breaking layout
  • Minimum text size recommendations for different content types
  • Sufficient contrast between text and background colors

Common Font Size Issues

  • Fixed font sizes that prevent user scaling
  • Too small text for important information
  • Inconsistent sizing across different devices
  • Poor readability at different zoom levels

Best Practices for Accessible Typography

1. Use Relative Units

Prefer relative units over fixed pixel sizes to ensure text scales properly across devices:

.text-responsive {
  /* Avoid fixed pixels */
  font-size: 16px; /* ❌ */
  
  /* Use relative units */
  font-size: 1rem;  /* ✅ */
  font-size: 1.25em; /* ✅ */
}

2. Establish a Clear Hierarchy

Create a consistent typographic scale that maintains readability at all sizes:

:root {
  --text-xs: 0.75rem;   /* 12px */
  --text-sm: 0.875rem;  /* 14px */
  --text-base: 1rem;    /* 16px */
  --text-lg: 1.125rem;  /* 18px */
  --text-xl: 1.25rem;   /* 20px */
  --text-2xl: 1.5rem;   /* 24px */
}

3. Consider Line Height

Maintain proper line spacing for optimal readability:

.readable-text {
  line-height: 1.5;
  max-width: 65ch;
  margin: 1em 0;
}

4. Support Text Spacing

Allow text spacing properties to be modified without breaking layout:

.adjustable-text {
  letter-spacing: normal;
  word-spacing: normal;
  line-height: normal;
  text-align: start;
}

Testing Font Size Accessibility

Browser Zoom Testing

Test your content at different zoom levels (100%, 150%, 200%) to ensure:

  • Text remains readable and properly formatted
  • No content is cut off or overlapping
  • Interactive elements remain functional
  • Layout maintains its structure

Device Testing

Check font sizes across different devices and screen sizes:

  • Desktop monitors at various resolutions
  • Mobile devices with different pixel densities
  • Tablets in both portrait and landscape orientations
  • Different operating systems and browsers

User Preference Testing

Verify text remains accessible when users modify their system preferences:

  • Browser font size settings
  • System-level text scaling
  • High contrast modes
  • Custom stylesheets

Related Tools and Resources

Frequently Asked Questions

What is the recommended minimum font size for body text?

The generally accepted minimum size for body text is 16 pixels (1rem). However, this can vary depending on the font family, as some fonts appear smaller or larger at the same pixel size. Always test readability with actual users and consider your target audience when making font size decisions.

How do I handle font sizes for different languages?

Different languages may require different font sizes to maintain readability. Consider these factors:

  • Character complexity (especially for languages like Chinese or Japanese)
  • Reading direction (LTR vs RTL)
  • Cultural preferences and expectations
  • Available font families for different scripts

Should I use pixels, rems, or ems for font sizes?

Each unit has its use case:

  • rems: Best for most text elements as they scale with user preferences
  • ems: Useful for components that should scale relative to their parent
  • pixels: Can be appropriate for minimal UI elements that should remain consistent

How do I maintain font size consistency across different devices?

Use these strategies to maintain consistency:

/* Base font size */
:root {
  font-size: 16px;
}

/* Responsive adjustments */
@media screen and (max-width: 768px) {
  :root {
    font-size: 14px;
  }
}

/* Use rem units for consistent scaling */
.text-element {
  font-size: 1rem;
  line-height: 1.5;
}

Accessibility Standards and Guidelines

WCAG Success Criteria

  • 1.4.4 Resize Text: Text can be resized without assistive technology up to 200% without loss of content or functionality
  • 1.4.8 Visual Presentation: Provides additional requirements for text presentation
  • 1.4.12 Text Spacing: No loss of content or functionality occurs when text spacing is adjusted

Implementation Techniques

/* Enable text spacing adjustments */
.accessible-text {
  /* Line height is at least 1.5 times the font size */
  line-height: 1.5;
  
  /* Paragraph spacing is at least 2 times the font size */
  margin-bottom: 2em;
  
  /* Letter spacing is at least 0.12 times the font size */
  letter-spacing: 0.12em;
  
  /* Word spacing is at least 0.16 times the font size */
  word-spacing: 0.16em;
}