#0187AF · #018C90
Four independent scores (read the one that fits your goal): Readability 0/100 (fail) · Harmony 80/100 (monochrome) · Distinguishable 26/100 (hard to tell apart) · Match 50/100 (different). There is no single “good/bad” — a pair can clash for text yet be great for an outfit.
Cerulean and Dark Cyan are a clear pair (ΔE 23). They have closely related hues (12° apart) and their lightness is similar, so they read as two same-weight colours.
Cerulean text on Dark Cyan: 1.01:1 (Fail); Dark Cyan text on Cerulean: 1.01:1 (Fail). Neither meets AA at body size — nudging one color to #001622 clears it.
Monochrome — monochrome — a recognised, balanced pairing (harmony 80/100). This is about how they look together (clothing, interiors, branding), independent of text contrast.
Not at body size — the best direction is only 1.0:1, below the 4.5:1 minimum. Nudging one colour to #001622 clears AA.
Their CIE76 ΔE is about 23 — a clear pair.
clearly different colours (ΔE 23).
Explore each color: Cerulean #0187AF · Dark Cyan #018C90 · Shades: Cerulean shades · Dark Cyan shades · Contrast checker →