#EFFF5B#EFFF5B

#EFFF5B is a very light, vivid yellow. Relative luminance 0.906; OKLCH L 95.9% C 0.183 H 114.7°. Best body text is #000000 at 19.13:1 contrast (WCAG AA passes).

Color values

HEX	#EFFF5B
RGB	rgb(239, 255, 91)
HSL	hsl(66, 100%, 68%)
HSV	hsv(66, 64%, 100%)
CMYK	cmyk(6.3%, 0%, 64.3%, 0%)
CIE-LAB	lab(96.26, -25.45, 73.53)
CIE-LCH	lch(96.26, 77.81, 109.10°)
OKLab	oklab(95.9% -0.0763 0.1662)
OKLCH	oklch(95.9% 0.183 114.7)
XYZ	xyz(73.2468, 90.6273, 23.5298)
Luminance	0.9063 (WCAG relative)
Temperature	warm
Family	yellow

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#EFFF5B #6B5BFF

analogous

#FFBD5B #EFFF5B #9DFF5B

triadic

#EFFF5B #5BEFFF #FF5BEF

tetradic

#EFFF5B #5BFFBD #6B5BFF #FF5B9D

square

#EFFF5B #5BFFBD #6B5BFF #FF5B9D

split-complementary

#EFFF5B #5B9DFF #BD5BFF

monochromatic

#CAE000 #E9FF1E #EFFF5B #F5FF98 #FBFFD5

Accessibility & contrast

On white

1.10

#EFFF5B on #FFFFFF

AA ✗AA large ✗AAA ✗

On black

19.13

#EFFF5B on #000000

AA ✓AA large ✓AAA ✓

Best text color

#000000 on #EFFF5B

19.13:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##EFFF5B	#FFFFFF	#000000	##000000
##EFFF5B	1.00	1.10	19.13	19.13
#FFFFFF	1.10	1.00	21.00	21.00
#000000	19.13	21.00	1.00	1.00
##000000	19.13	21.00	1.00	1.00

Color blindness preview

Protanopia (red-blind)

#FFF344

Deuteranopia (green-blind)

#FFF666

Tritanopia (blue-blind)

#FEF1DE

Achromatopsia (no color)

#F4F4F4

Design tokens & code

CSS

--color: #efff5b;
/* rgb */ color: rgb(239, 255, 91);
/* oklch */ color: oklch(95.9% 0.183 114.7);

Tailwind

colors: {
  custom: {
    50: '#f8ff91',
    500: '#efff5b',
    950: '#000000',
  },
}

SCSS

$custom: #efff5b;
$custom-light: #f8ff91;
$custom-dark: #000000;

JSON

{
  "hex": "#efff5b",
  "rgb": {
    "r": 239,
    "g": 255,
    "b": 91
  },
  "hsl": {
    "h": 65.854,
    "s": 100,
    "l": 67.843
  },
  "oklch": {
    "l": 0.95897,
    "c": 0.18286,
    "h": 114.7
  },
  "luminance": 0.90626
}

Semantic roles & 50–950 ramp

primary

#EFFF5B

secondary

#3726D8

accent

#00E616

background

#FFFFFC

surface

#FFFFF4

border

#D7D7CE

text

#18170D

muted

#86857F

Preview Lab

Preview with #EFFF5B

Body copy rendered with the generated semantic roles for this colour.

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