Unmellow Yellow

#FFFF66

Crayola color

Unmellow Yellow (#FFFF66) is a bright, vivid lemon-yellow in the Crayola palette, lighter and more neon-adjacent than standard yellow with a slightly greener cast that gives it a fluorescent quality. The playful name inverts the concept of mellow, suggesting a yellow that is explicitly bright, energetic, and alert rather than calm or golden. Used in illustration for neon effects, electric accents, and maximally cheerful, upbeat colour work.

Color Values

HEX

#FFFF66

RGB

255, 255, 102

HSL

60.0, 100.0%, 70.0%

HSV

60.0, 60.0%, 100.0%

CMYK

0.0%, 0.0%, 60.0%, 0.0%

OKLCH

0.9723 0.1713 109.2

Properties

Color Psychology

Pale yellows and creams evoke sunlight, freshness, and intellectual clarity. They are the lightest chromatic colors the eye perceives, creating a sense of spaciousness and openness. Light yellow is often associated with new beginnings and gentle happiness.

Design Usage

Light yellows are excellent for background tints, highlight markers, and information callout boxes. They add warmth to white-dominated layouts without overwhelming the content hierarchy. Use them cautiously for text backgrounds since pale yellow on white creates poor contrast ratios.

Color Harmonies

Color Blindness Simulation

CSS Usage

background-color: #FFFF66;
color: #FFFF66;
border-color: #FFFF66;
Nearest Tailwind: Yellow 300 #FDE047

Tailwind Shades

Contrast Checker

Text on white

1.06:1

AA Fail AAA Fail

Text on black

19.75:1

AA Pass AAA Pass

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