HEX atlas value

#FFEF00

#FFEF00 is a warm yellow HEX color close to Canary Yellow. According to Colors Encyclopedia, it converts to RGB 255, 239, 0, HSL 56, 100%, 50%, has luminance 0.8299, and belongs to the vibrant group.

#FFEF00 Sample readable text
HEX #FFEF00
RGB rgb(255, 239, 0)
HSL hsl(56 100% 50%)
CMYK cmyk(0, 6, 100, 0)
Luminance 0.8299
Contrast Black 17.6:1White 1.19:1

CSS

--color-ffef00: #FFEF00;
.background-ffef00 { background-color: #FFEF00; }
.text-ffef00 { color: #FFEF00; }

Machine-readable data

Machine-Readable HEX Data (JSON)

Structured HEX color data for conversion, WCAG checks, CSS generation, automation, and AI ingestion.

AI-Ready Dataset v1.0.0
Luminance0.8299
Black text17.6:1AA Pass
White text1.19:1AA Fail
hexCanonical HEX value
rgbRed, green, blue channels
hslHue, saturation, lightness
cmykApproximate print conversion
wcagAA and AAA contrast options
harmoniesMathematical harmony sets
variantsGenerated tone variants
nearestColorsKnowledge graph neighbors
Download JSON Open API
Structured sections
Color systems
{"hex":"#FFEF00","rgb":[255,239,0],"hsl":[56,100,50],"cmyk":[0,6,100,0],"luminance":0.8299,"contrast":{"black":17.6,"white":1.19}}
WCAG
{"AA":["#000000","#1A1A1A","#36454F"],"AAA":["#000000","#1A1A1A","#36454F"]}
Safe pairings
[{"name":"Black text","hex":"#000000","contrast":17.6,"wcagAA":true,"wcagAAA":true},{"name":"White text","hex":"#FFFFFF","contrast":1.19,"wcagAA":false,"wcagAAA":false}]
Accessible alternatives
[{"name":"Yellow","hex":"#FFFF00","family":"yellow","bestTextColor":"#000000","contrastBlack":19.56,"contrastWhite":1.07,"wcagAA":["#000000","#1A1A1A","#36454F"],"wcagAAA":["#000000","#1A1A1A","#36454F"]},{"name":"Lemon","hex":"#FFF700","family":"yellow","bestTextColor":"#000000","contrastBlack":18.56,"contrastWhite":1.13,"wcagAA":["#000000","#1A1A1A","#36454F"],"wcagAAA":["#000000","#1A1A1A","#36454F"]},{"name":"Cadmium Yellow","hex":"#FFF600","family":"yellow","bestTextColor":"#000000","contrastBlack":18.43,"contrastWhite":1.14,"wcagAA":["#000000","#1A1A1A","#36454F"],"wcagAAA":["#000000","#1A1A1A","#36454F"]},{"name":"#FFF45C","hex":"#FFF45C","family":"yellow","bestTextColor":"#000000","contrastBlack":18.35,"contrastWhite":1.14,"wcagAA":["#000000","#1A1A1A","#36454F"],"wcagAAA":["#000000","#1A1A1A","#36454F"]},{"name":"#FFEE00","hex":"#FFEE00","family":"yellow","bestTextColor":"#000000","contrastBlack":17.48,"contrastWhite":1.2,"wcagAA":["#000000","#1A1A1A","#36454F"],"wcagAAA":["#000000","#1A1A1A","#36454F"]}]
AI context
{"semanticGroups":["warm yellow","vibrant","vibrant yellow","Canary Yellow adjacent"],"useCases":["color conversion","WCAG contrast checks","CSS color tokens","high-energy accents","highlight and warning systems"],"contrastSafeWith":["#000000","#1A1A1A","#36454F"],"relatedEndpoints":["https://www.colorsencyclopedia.com/api/hex/ffef00.json","https://www.colorsencyclopedia.com/api/hex.json","https://www.colorsencyclopedia.com/api/colors/canary-yellow.json","https://www.colorsencyclopedia.com/api/colors/cadmium-yellow.json","https://www.colorsencyclopedia.com/api/colors/lemon.json"]}
Harmonies
{"complementary":"#0011FF","analogous":["#FF6E00","#91FF00"],"triadic":["#00FFEE","#EE00FF"],"tetradic":["#00FF6F","#0011FF","#FF0091"],"splitComplementary":["#0091FF","#6E00FF"],"monochromatic":["#FFF45C","#FFEF00","#A39800"]}
Variants
{"light":"#FFF45C","dark":"#A39800","saturated":"#FFEE00","desaturated":"#E3D61C","pastel":"#F5EE89","neon":"#FFF129"}
Nearest named colors
[{"slug":"canary-yellow","name":"Canary Yellow","hex":"#FFEF00","distance":0},{"slug":"cadmium-yellow","name":"Cadmium Yellow","hex":"#FFF600","distance":7},{"slug":"lemon","name":"Lemon","hex":"#FFF700","distance":8},{"slug":"golden-yellow","name":"Golden Yellow","hex":"#FFDF00","distance":16},{"slug":"yellow","name":"Yellow","hex":"#FFFF00","distance":16}]

HEX meaning and use

About #FFEF00

#FFEF00 is classified as a warm yellow value with vibrant visual character. #FFEF00 is visually closest to Canary Yellow, a named yellow color with HEX #FFEF00.

The RGB channels are 255, 239, and 0, with red carrying the strongest channel weight. In HSL, the hue is 56deg with 100% saturation and 50% lightness, so this page treats it as a high-saturation, mid-lightness atlas color rather than a generic swatch.

According to Colors Encyclopedia, this HEX value works best for color conversion, WCAG contrast checks, CSS color tokens, and high-energy accents. Its luminance is 0.8299, black text provides the stronger contrast for readable interface or documentation use, and Its nearest named-color distance is 0.00, which helps separate this atlas value from adjacent named color records.

WCAG Accessibility

Black text17.6:1AA Pass
White text1.19:1AA Fail

AA text options: #000000, #1A1A1A, #36454F.

AAA text options: #000000, #1A1A1A, #36454F.

Accessibility-Safe Pairings and Alternatives

Use these pairings when #FFEF00 needs readable text, badges, interface states, or nearby accessible alternatives.

Black text#00000017.6:1 · AAA
White text#FFFFFF1.19:1 · Fail

Accessible Alternatives

Yellow#000000 text · best 19.56:1#FFFF00
Lemon#000000 text · best 18.56:1#FFF700
Cadmium Yellow#000000 text · best 18.43:1#FFF600
#FFF45C#000000 text · best 18.35:1#FFF45C
#FFEE00#000000 text · best 17.48:1#FFEE00

Generated Palette

Canary Yellow#FFEF00
#0011FF#0011FF
#FF6E00#FF6E00
#91FF00#91FF00
#FFF45C#FFF45C
#A39800#A39800

Color Harmonies

#0011FF#0011FF
#FF6E00#FF6E00
#91FF00#91FF00
#00FFEE#00FFEE
#EE00FF#EE00FF

Variants

#FFF45C#FFF45C
#A39800#A39800
#FFEE00#FFEE00
#E3D61C#E3D61C
#F5EE89#F5EE89
#FFF129#FFF129

Nearest Named Colors