HEX atlas value

#EFFA19

#EFFA19 is a warm yellow HEX color close to Neon Yellow. According to Colors Encyclopedia, it converts to RGB 239, 250, 25, HSL 63, 96%, 54%, has luminance 0.8679, and belongs to the vibrant group.

yellow warm vibrant

#EFFA19 Sample readable text

HEX #EFFA19

RGB rgb(239, 250, 25)

HSL hsl(63 96% 54%)

CMYK cmyk(4, 0, 90, 2)

Luminance 0.8679

Contrast Black 18.36:1White 1.14:1

CSS

--color-effa19: #EFFA19;
.background-effa19 { background-color: #EFFA19; }
.text-effa19 { color: #EFFA19; }

Luminance0.8679

Black text18.36:1AA Pass

White text1.14:1AA 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

Structured sections

Color systems

{"hex":"#EFFA19","rgb":[239,250,25],"hsl":[63,96,54],"cmyk":[4,0,90,2],"luminance":0.8679,"contrast":{"black":18.36,"white":1.14}}

WCAG

{"AA":["#000000","#1A1A1A","#36454F"],"AAA":["#000000","#1A1A1A","#36454F"]}

Safe pairings

[{"name":"Black text","hex":"#000000","contrast":18.36,"wcagAA":true,"wcagAAA":true},{"name":"White text","hex":"#FFFFFF","contrast":1.14,"wcagAA":false,"wcagAAA":false}]

Accessible alternatives

[{"name":"Daffodil","hex":"#FFFF31","family":"yellow","bestTextColor":"#000000","contrastBlack":19.6,"contrastWhite":1.07,"wcagAA":["#000000","#1A1A1A","#36454F"],"wcagAAA":["#000000","#1A1A1A","#36454F"]},{"name":"#F3FF14","hex":"#F3FF14","family":"yellow","bestTextColor":"#000000","contrastBlack":19.13,"contrastWhite":1.1,"wcagAA":["#000000","#1A1A1A","#36454F"],"wcagAAA":["#000000","#1A1A1A","#36454F"]},{"name":"#F5FC73","hex":"#F5FC73","family":"yellow","bestTextColor":"#000000","contrastBlack":19.05,"contrastWhite":1.1,"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":"Chartreuse Green","hex":"#DFFF00","family":"yellow","bestTextColor":"#000000","contrastBlack":18.44,"contrastWhite":1.14,"wcagAA":["#000000","#1A1A1A","#36454F"],"wcagAAA":["#000000","#1A1A1A","#36454F"]}]

AI context

{"semanticGroups":["warm yellow","vibrant","vibrant yellow","Neon 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/effa19.json","https://www.colorsencyclopedia.com/api/hex.json","https://www.colorsencyclopedia.com/api/colors/neon-yellow.json","https://www.colorsencyclopedia.com/api/colors/daffodil.json","https://www.colorsencyclopedia.com/api/colors/lemon.json"]}

Harmonies

{"complementary":"#2419FA","analogous":["#FA9519","#7EFA19"],"triadic":["#19EFFA","#FA19EF"],"tetradic":["#19FA95","#2419FA","#FA197E"],"splitComplementary":["#197EFA","#9519FA"],"monochromatic":["#F5FC73","#EFFA19","#ABB404"]}

Variants

{"light":"#F5FC73","dark":"#ABB404","saturated":"#F3FF14","desaturated":"#D8E133","pastel":"#F0F59E","neon":"#F5FF3D"}

Nearest named colors

[{"slug":"neon-yellow","name":"Neon Yellow","hex":"#FFF01F","distance":19.79898987322333},{"slug":"daffodil","name":"Daffodil","hex":"#FFFF31","distance":29.274562336608895},{"slug":"lemon","name":"Lemon","hex":"#FFF700","distance":29.832867780352597},{"slug":"cadmium-yellow","name":"Cadmium Yellow","hex":"#FFF600","distance":29.949958263743873},{"slug":"chartreuse-green","name":"Chartreuse Green","hex":"#DFFF00","distance":30.099833886584822}]

HEX meaning and use

About #EFFA19

#EFFA19 is classified as a warm yellow value with vibrant visual character. #EFFA19 is visually closest to Neon Yellow, a named yellow color with HEX #FFF01F.

The RGB channels are 239, 250, and 25, with green carrying the strongest channel weight. In HSL, the hue is 63deg with 96% saturation and 54% 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 0.8679, black text provides the stronger contrast for readable interface or documentation use, and Its nearest named-color distance is 19.80, which helps separate this atlas value from adjacent named color records.

WCAG Accessibility

Black text18.36:1AA Pass

White text1.14:1AA Fail

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

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

Accessibility-Safe Pairings and Alternatives

Use these pairings when #EFFA19 needs readable text, badges, interface states, or nearby accessible alternatives.

Black text#00000018.36:1 · AAA

White text#FFFFFF1.14:1 · Fail

Accessible Alternatives

Daffodil#000000 text · best 19.6:1#FFFF31

#F3FF14#000000 text · best 19.13:1#F3FF14

#F5FC73#000000 text · best 19.05:1#F5FC73

Lemon#000000 text · best 18.56:1#FFF700

Chartreuse Green#000000 text · best 18.44:1#DFFF00

Generated Palette

#EFFA19#EFFA19

#2419FA#2419FA

#FA9519#FA9519

#7EFA19#7EFA19

#F5FC73#F5FC73

#ABB404#ABB404

Color Harmonies

#2419FA#2419FA

#FA9519#FA9519

#7EFA19#7EFA19

#19EFFA#19EFFA

#FA19EF#FA19EF

Variants

#F5FC73#F5FC73

#ABB404#ABB404

#F3FF14#F3FF14

#D8E133#D8E133

#F0F59E#F0F59E

#F5FF3D#F5FF3D

Nearest Named Colors

Neon Yellow#FFF01F

Daffodil#FFFF31

Lemon#FFF700

Cadmium Yellow#FFF600

Chartreuse Green#DFFF00

#EFFA19

CSS

Machine-Readable HEX Data (JSON)

About #EFFA19

WCAG Accessibility

Accessibility-Safe Pairings and Alternatives

Accessible Alternatives

Generated Palette

Color Harmonies

Variants

Nearest Named Colors

Related HEX Guides