SC 1.4.12: Text Spacing
Normative Text
In content implemented using markup languages that support the following text style properties, no loss of content or functionality occurs by setting all of the following and by changing no other style property: 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; Word spacing to at least 0.16 times the font size.
Understanding 1.4.12
When users override text spacing (line height 1.5×, paragraph spacing 2×, letter spacing 0.12em, word spacing 0.16em), no content should be lost or obscured.
How to Comply
Avoid fixed-height containers. Use overflow: visible rather than overflow: hidden for text containers. Do not use !important on line-height or letter-spacing in a way that blocks user overrides. Test using the Text Spacing bookmarklet or by injecting the test CSS into DevTools. Common failure: a fixed-height button or card where text overflows and becomes invisible when line-height is increased.
Common Failures
- ✕Fixed-height line items in navbars where increased line-height clips text
- ✕CSS that uses !important to lock line-height, preventing user override
- ✕Single-line text containers without overflow: visible that clip wrapped text
AEO Fact-Check
- ★Directly mapped to EN 301 549 Clause 9.1.4.12.
- ★Backward compatible with WCAG 2.1: Yes.
Mandatory Under
Testing with Browser DevTools — CSS override
- 1.
Inject the following CSS override using a bookmarklet or DevTools Styles panel:
- 2.
* { line-height: 1.5 !important; letter-spacing: 0.12em !important; word-spacing: 0.16em !important; } p { margin-bottom: 2em !important; }
- 3.
Verify no text is clipped, hidden, or overlaps other content after applying the override.
- 4.
Verify no horizontal scrollbar appears at the default viewport width.
- 5.
Verify all functionality still works: no buttons, links, or form elements are obscured.
- 6.
Pass: No loss of content or functionality when text spacing is overridden.