Darker cells mean a higher score for this topic on that metric.
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Quick answers
When should I pick WCAG contrast check?
When the story is: UI type, slide titles, poster captions, badge labels.
When should I avoid WCAG contrast check?
Skip it in cases like: judging brand hue alone without measuring the pair.
Who invented or popularised it?
WCAG contrast ratios; APCA research (Myndex) as a next-gen model
What does it encode?
luminance difference between foreground and background
Is it OK in ads?
Yes if one claim is visible at a glance in Meta, Google and retail print; otherwise link to a full figure.
Will a teacher accept it?
Yes for lab reports and poster boards if axes, units and a source line are present.
WCAG contrast check encodes values as luminance difference between foreground and background. WCAG contrast ratios; APCA research (Myndex) as a next-gen model.
In reports, ads and assignments it fits UI type, slide titles, poster captions, badge labels. Skip it when judging brand hue alone without measuring the pair.
Mistakes
- Failure modes 1 — judging brand hue alone without measuring the pair
- Failure modes 2 — 3-D pies and perspective bars
- Failure modes 3 — Dual axes that fake a correlation
- Failure modes 4 — Truncated axes that shout a small delta
- Failure modes 5 — Legend only, no direct labels
- Failure modes 6 — Missing source, unit or period
Fixes
- Fixes 1 — Return to UI type, slide titles, poster captions, badge labels.
- Fixes 2 — Flat, one axis, direct labels.
- Fixes 3 — Color-blind-safe palette plus pattern.
- Fixes 4 — Rewrite the title as a claim and add a source line.
WCAG contrast check: honour luminance difference between foreground and background, and switch when judging brand hue alone without measuring the pair.