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.
Principles
- Encoding — The core mark of WCAG contrast check is luminance difference between foreground and background.
- History — WCAG contrast ratios; APCA research (Myndex) as a next-gen model
- Fit — UI type, slide titles, poster captions, badge labels
- Shared baseline — The eye compares length and position more accurately than area.
- Audience — PowerPoint, Excel or Google Sheets and Meta, Google and retail print share the same geometry.
Misconceptions
- Pretty equals true — Decoration rarely persuades; it slows reading.
- 3-D helps — Perspective distortion wrecks comparison. Keep it flat.
- More series is richer — Do not stack stories. One WCAG contrast check, one claim.
- Default palette is fine — Rainbow defaults fail color-blind viewers and grey print. Change Excel or Google Sheets defaults.
Why it matters
- Work — Work: UI type, slide titles, poster captions, badge labels. Readable in four minutes in PowerPoint.
- Ads — Ads: one number and one shape speak first in Meta, Google and retail print.
- School — School: for lab reports and poster boards, pick the form that answers the rubric.
- Craft — Craft: honour luminance difference between foreground and background and decoration falls away.
WCAG contrast check: honour luminance difference between foreground and background, and switch when judging brand hue alone without measuring the pair.