Which contrast and text-spacing thresholds are normative today under WCAG 2.2 (1.4.3, 1.4.6, 1.4.11, 1.4.12), how are ratios computed, and what level is each?
WCAG 2.2 (REC, 12 Dec 2024) defines contrast as (L1+0.05)/(L2+0.05) on relative luminance and requires 4.5:1 for text and 3:1 for large text (18 pt or 14 pt bold) at AA (SC 1.4.3), 7:1 and 4.5:1 at AAA (SC 1.4.6), 3:1 for UI components and meaningful graphics against adjacent colours (SC 1.4.11), and no loss of content when users set line height 1.5, paragraph spacing 2, letter spacing 0.12 and word spacing 0.16 times the font size (SC 1.4.12). The text scopes these to web content; applying them to video, print or images is an extension.
WCAG 2.2 (REC, 12 Dec 2024) defines contrast as (L1+0.05)/(L2+0.05) on relative luminance and requires 4.5:1 for text and 3:1 for large text (18 pt or 14 pt bold) at AA (SC 1.4.3), 7:1 and 4.5:1 at AAA (SC 1.4.6), 3:1 for UI components and meaningful graphics against adjacent colours (SC 1.4.11), and no loss of content when users set line height 1.5, paragraph spacing 2, letter spacing 0.12 and word spacing 0.16 times the font size (SC 1.4.12). The text scopes these to web content; applying them to video, print or images is an extension.
Curator qualifications: Recommendation read 2026-10-22; nothing measured; not legal advice on applicability. APCA or other draft methods are not normative here.
Limitations: Recommendation read 2026-10-22; nothing measured; not legal advice on applicability.
Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.
Structured fields
{
"citations": [
{
"url": "https://www.w3.org/TR/WCAG22/",
"note": "w3.org/TR/WCAG22 (REC 2024-12-12): SC 1.4.3, 1.4.6, 1.4.11, 1.4.12; definitions of contrast ratio and large scale"
},
{
"url": "https://www.w3.org/WAI/WCAG22/Understanding/contrast-minimum.html",
"note": "w3.org/TR/WCAG22 (REC 2024-12-12): SC 1.4.3, 1.4.6, 1.4.11, 1.4.12; definitions of contrast ratio and large scale"
}
]
}Evidence claims
- [sourced_fact] WCAG 2.2 (REC, 12 Dec 2024) defines contrast as (L1+0.05)/(L2+0.05) on relative luminance and requires 4.5:1 for text and 3:1 for large text (18 pt or 14 pt bold) at AA (SC 1.4.3), 7:1 and 4.5:1 at AAA (SC 1.4.6), 3:1 for UI components and meaningful graphics against adjacent colours (SC 1.4.11), and no loss of content when users set line height 1.5, paragraph spacing 2, letter spacing 0.12 and word spacing 0.16 times the font size (SC 1.4.12). The text scopes these to web content; applying them to video, print or images is an extension. · locator: w3.org/TR/WCAG22 (REC 2024-12-12): SC 1.4.3, 1.4.6, 1.4.11, 1.4.12; definitions of contrast ratio and large scale source
Rights
| component | license | hosting | redistribution | modification | training | Evidence and notes |
|---|---|---|---|---|---|---|
| documentation | unknown | permitted | permitted | unknown | unknown | Applies to this original summary only, not to the cited sources. |