WCAG 1.4.12 Text Spacing: Support Custom Text Spacing Overrides

What This Criterion Requires

WCAG 1.4.12 requires that no loss of content or functionality occurs when users override the following text style properties: line height (line spacing) to at least 1.5 times the font size, spacing following paragraphs to at least 2 times the font size, letter spacing (tracking) to at least 0.12 times the font size, and word spacing to at least 0.16 times the font size. This criterion was added in WCAG 2.1 to support users with dyslexia and low vision who need additional spacing to read text comfortably. The criterion does not require that content be presented with these spacings by default, only that content remains usable when a user applies these overrides through a browser extension, custom stylesheet, or other user agent mechanism. Content must not be clipped, truncated, or overlapped when these spacing values are applied. Developers must avoid fixed-height containers, overflow:hidden on text elements, and layouts that break when text takes up more vertical or horizontal space.

Why It Matters

People with dyslexia, low vision, and certain cognitive disabilities often need to increase the spacing between lines, words, and letters to be able to read text. Research shows that increased text spacing significantly improves reading speed and comprehension for people with dyslexia. Without adequate spacing, letters and words can appear to run together, making it extremely difficult to track individual words and lines. Low-vision users may increase spacing to reduce crowding effects that make text harder to distinguish. When websites use fixed containers that clip text or layouts that break when spacing is increased, these users lose access to content even though they are using legitimate accessibility tools and techniques. The specific spacing values in this criterion are based on accessibility research and represent the minimum spacing adjustments that many users need. Supporting these overrides is a matter of building flexible layouts that accommodate user preferences rather than rigidly constraining text presentation.

Common Failures and How to Fix Them

<style>
.testimonial-card {
  height: 150px;
  overflow: hidden;
  padding: 1rem;
}
</style>
<div class="testimonial-card">
  <p>This product changed my workflow completely. I cannot recommend it enough to anyone looking for a better solution.</p>
  <p class="author">-- Jane Smith, Designer</p>
</div>

<style>
.testimonial-card {
  min-height: 150px;
  overflow: visible;
  padding: 1rem;
}
</style>
<div class="testimonial-card">
  <p>This product changed my workflow completely. I cannot recommend it enough to anyone looking for a better solution.</p>
  <p class="author">-- Jane Smith, Designer</p>
</div>

<style>
body {
  line-height: 1.2 !important;
  letter-spacing: 0 !important;
  word-spacing: 0 !important;
}
p {
  margin-bottom: 5px !important;
}
</style>

<style>
body {
  line-height: 1.5;
  letter-spacing: normal;
  word-spacing: normal;
}
p {
  margin-bottom: 1em;
}
/* Avoid !important on text spacing properties
   to allow user stylesheet overrides */
</style>

How to Test

1. Apply the WCAG text spacing bookmarklet (available at various accessibility resource sites) which sets line-height to 1.5, paragraph spacing to 2em, letter-spacing to 0.12em, and word-spacing to 0.16em.
2. Verify that all text content remains fully visible and no text is clipped, truncated, or overlapping with other elements.
3. Check that all interactive elements remain functional and that clickable areas have not shifted or become inaccessible.
4. Review the CSS for fixed-height containers with overflow:hidden that contain text, and for text spacing properties set with !important.

CMS-Specific Guidance

This criterion commonly causes issues on these platforms:

• Wordpress Accessibility Checklist
• Shopify Accessibility Checklist
• Squarespace Accessibility Checklist
• Wix Accessibility Checklist
• Webflow Accessibility Checklist
• Framer Accessibility Checklist

Further Reading

• Wcag Explained Plain English
• Five Minute Accessibility Audit

Related WCAG Criteria

• WCAG 1.4.4
• WCAG 1.4.10