#CCB600 · #FFFFFF
Four independent scores (read the one that fits your goal): Readability 21/100 (fail) · Harmony 62/100 (analogous (soft)) · Distinguishable 100/100 (easy to tell apart) · Match 0/100 (different). There is no single “good/bad” — a pair can clash for text yet be great for an outfit.
Vivid Yellow and White are very different (ΔE 80). They have distinctly different hues (54° apart) and their lightness is different, giving a clear light/dark split.
Vivid Yellow text on White: 2.05:1 (Fail); White text on Vivid Yellow: 2.05:1 (Fail). Neither meets AA at body size — nudging one color to #867700 clears it.
Analogous (soft) — workable but not a textbook harmony (harmony 62/100). This is about how they look together (clothing, interiors, branding), independent of text contrast.
Not at body size — the best direction is only 2.0:1, below the 4.5:1 minimum. Nudging one colour to #867700 clears AA.
Their CIE76 ΔE is about 80 — very different.
clearly different colours (ΔE 80).
Explore each color: Vivid Yellow #CCB600 · White #FFFFFF · Shades: Vivid Yellow shades · White shades · Contrast checker →