#EFFF40#EFFF40

#EFFF40 is a very light, vivid yellow. Relative luminance 0.902; OKLCH L 95.7% C 0.199 H 114.5°. Best body text is #000000 at 19.05:1 contrast (WCAG AA passes).

Color values

HEX	#EFFF40
RGB	rgb(239, 255, 64)
HSL	hsl(65, 100%, 63%)
HSV	hsv(65, 75%, 100%)
CMYK	cmyk(6.3%, 0%, 74.9%, 0%)
CIE-LAB	lab(96.10, -26.79, 82.58)
CIE-LCH	lch(96.10, 86.81, 107.97°)
OKLab	oklab(95.72% -0.0823 0.181)
OKLCH	oklch(95.72% 0.199 114.5)
XYZ	xyz(72.2842, 90.2423, 18.4602)
Luminance	0.9024 (WCAG relative)
Temperature	warm
Family	yellow

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#EFFF40 #5040FF

analogous

#FFAF40 #EFFF40 #90FF40

triadic

#EFFF40 #40EFFF #FF40EF

tetradic

#EFFF40 #40FFAF #5040FF #FF4090

square

#EFFF40 #40FFAF #5040FF #FF4090

split-complementary

#EFFF40 #4090FF #AF40FF

monochromatic

#B4C500 #EAFF03 #EFFF40 #F4FF7D #F9FFBA

Accessibility & contrast

On white

1.10

#EFFF40 on #FFFFFF

AA ✗AA large ✗AAA ✗

On black

19.05

#EFFF40 on #000000

AA ✓AA large ✓AAA ✓

Best text color

#000000 on #EFFF40

19.05:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##EFFF40	#FFFFFF	#000000	##000000
##EFFF40	1.00	1.10	19.05	19.05
#FFFFFF	1.10	1.00	21.00	21.00
#000000	19.05	21.00	1.00	1.00
##000000	19.05	21.00	1.00	1.00

Color blindness preview

Protanopia (red-blind)

#FFF208

Deuteranopia (green-blind)

#FFF551

Tritanopia (blue-blind)

#FFF0DB

Achromatopsia (no color)

#F4F4F4

Design tokens & code

CSS

--color: #efff40;
/* rgb */ color: rgb(239, 255, 64);
/* oklch */ color: oklch(95.7% 0.199 114.5);

Tailwind

colors: {
  custom: {
    50: '#f8ff83',
    500: '#efff40',
    950: '#000000',
  },
}

SCSS

$custom: #efff40;
$custom-light: #f8ff83;
$custom-dark: #000000;

JSON

{
  "hex": "#efff40",
  "rgb": {
    "r": 239,
    "g": 255,
    "b": 64
  },
  "hsl": {
    "h": 65.026,
    "s": 100,
    "l": 62.549
  },
  "oklch": {
    "l": 0.95718,
    "c": 0.19886,
    "h": 114.5
  },
  "luminance": 0.90241
}

Semantic roles & 50–950 ramp

primary

#EFFF40

secondary

#2F22C1

accent

#00E613

background

#FFFFFC

surface

#FFFFF4

border

#D7D7CE

text

#18170C

muted

#86857F

Preview Lab

Preview with #EFFF40

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

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