HEX atlas value

#C51D11

#C51D11 is a warm red HEX color close to Venetian Red. According to Colors Encyclopedia, it converts to RGB 197, 29, 17, HSL 4, 84%, 42%, has luminance 0.1279, and belongs to the vibrant group.

red warm vibrant

#C51D11 Sample readable text

HEX #C51D11

RGB rgb(197, 29, 17)

HSL hsl(4 84% 42%)

CMYK cmyk(0, 85, 91, 23)

Luminance 0.1279

Contrast Black 3.56:1White 5.9:1

CSS

--color-c51d11: #C51D11;
.background-c51d11 { background-color: #C51D11; }
.text-c51d11 { color: #C51D11; }

Luminance0.1279

Black text3.56:1AA Fail

White text5.9:1AA Pass

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":"#C51D11","rgb":[197,29,17],"hsl":[4,84,42],"cmyk":[0,85,91,23],"luminance":0.1279,"contrast":{"black":3.56,"white":5.9}}

WCAG

{"AA":["#FFFFFF","#F5F5F5"],"AAA":[]}

Safe pairings

[{"name":"Black text","hex":"#000000","contrast":3.56,"wcagAA":false,"wcagAAA":false},{"name":"White text","hex":"#FFFFFF","contrast":5.9,"wcagAA":true,"wcagAAA":false}]

Accessible alternatives

[{"name":"#71110A","hex":"#71110A","family":"red","bestTextColor":"#FFFFFF","contrastBlack":1.79,"contrastWhite":11.76,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF","#F5F5F5"]},{"name":"#11B9C5","hex":"#11B9C5","family":"cyan","bestTextColor":"#000000","contrastBlack":8.77,"contrastWhite":2.39,"wcagAA":["#000000","#1A1A1A"],"wcagAAA":["#000000","#1A1A1A"]},{"name":"Pompeian Red","hex":"#A42A04","family":"red","bestTextColor":"#FFFFFF","contrastBlack":2.91,"contrastWhite":7.21,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF"]},{"name":"Tool Red","hex":"#B11226","family":"red","bestTextColor":"#FFFFFF","contrastBlack":2.98,"contrastWhite":7.04,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF"]},{"name":"Firebrick","hex":"#B22222","family":"red","bestTextColor":"#FFFFFF","contrastBlack":3.14,"contrastWhite":6.68,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":[]}]

AI context

{"semanticGroups":["warm red","vibrant","vibrant red","Venetian Red adjacent"],"useCases":["color conversion","WCAG contrast checks","CSS color tokens","high-energy accents","high-attention visual states"],"contrastSafeWith":["#FFFFFF","#F5F5F5"],"relatedEndpoints":["https://www.colorsencyclopedia.com/api/hex/c51d11.json","https://www.colorsencyclopedia.com/api/hex.json","https://www.colorsencyclopedia.com/api/colors/venetian-red.json","https://www.colorsencyclopedia.com/api/colors/firebrick.json","https://www.colorsencyclopedia.com/api/colors/traffic-red.json"]}

Harmonies

{"complementary":"#11B9C5","analogous":["#C5115F","#C57711"],"triadic":["#11C51D","#1D11C5"],"tetradic":["#5FC511","#11B9C5","#7711C5"],"splitComplementary":["#11C577","#115FC5"],"monochromatic":["#EF4F43","#C51D11","#71110A"]}

Variants

{"light":"#EF4F43","dark":"#71110A","saturated":"#D60E00","desaturated":"#AE3229","pastel":"#E57971","neon":"#FF1100"}

Nearest named colors

[{"slug":"venetian-red","name":"Venetian Red","hex":"#C80815","distance":21.587033144922902},{"slug":"firebrick","name":"Firebrick","hex":"#B22222","distance":25.98076211353316},{"slug":"traffic-red","name":"Traffic Red","hex":"#CC0605","distance":26.870057685088806},{"slug":"tool-red","name":"Tool Red","hex":"#B11226","distance":31.016124838541646},{"slug":"pompeian-red","name":"Pompeian Red","hex":"#A42A04","distance":37.77565353504821}]

HEX meaning and use

About #C51D11

#C51D11 is classified as a warm red value with vibrant visual character. #C51D11 is visually closest to Venetian Red, a named red color with HEX #C80815.

The RGB channels are 197, 29, and 17, with red carrying the strongest channel weight. In HSL, the hue is 4deg with 84% saturation and 42% 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 0.1279, white text provides the stronger contrast for readable interface or documentation use, and Its nearest named-color distance is 21.59, which helps separate this atlas value from adjacent named color records.

WCAG Accessibility

Black text3.56:1AA Fail

White text5.9:1AA Pass

AA text options: #FFFFFF, #F5F5F5.

AAA text options: none in seed set.

Accessibility-Safe Pairings and Alternatives

Use these pairings when #C51D11 needs readable text, badges, interface states, or nearby accessible alternatives.

Black text#0000003.56:1 · Fail

White text#FFFFFF5.9:1 · AA

Accessible Alternatives

#71110A#FFFFFF text · best 11.76:1#71110A

#11B9C5#000000 text · best 8.77:1#11B9C5

Pompeian Red#FFFFFF text · best 7.21:1#A42A04

Tool Red#FFFFFF text · best 7.04:1#B11226

Firebrick#FFFFFF text · best 6.68:1#B22222

Generated Palette

#C51D11#C51D11

#11B9C5#11B9C5

#C5115F#C5115F

#C57711#C57711

#EF4F43#EF4F43

#71110A#71110A

Color Harmonies

#11B9C5#11B9C5

#C5115F#C5115F

#C57711#C57711

#11C51D#11C51D

#1D11C5#1D11C5

Variants

#EF4F43#EF4F43

#71110A#71110A

#D60E00#D60E00

#AE3229#AE3229

#E57971#E57971

#FF1100#FF1100

Nearest Named Colors

Venetian Red#C80815

Firebrick#B22222

Traffic Red#CC0605

Tool Red#B11226

Pompeian Red#A42A04

#C51D11

CSS

Machine-Readable HEX Data (JSON)

About #C51D11

WCAG Accessibility

Accessibility-Safe Pairings and Alternatives

Accessible Alternatives

Generated Palette

Color Harmonies

Variants

Nearest Named Colors

Related HEX Guides