HEX atlas value

#0057B8

#0057B8 is a cool blue HEX color nearest Signal Blue. RGB 0, 87, 184, HSL 212° 100% 36%, luminance 0.1028; view contrast and conversions.

blue cool vibrant jewel-tone

#0057B8 Sample readable text

HEX #0057B8

RGB rgb(0, 87, 184)

HSL hsl(212 100% 36%)

CMYK cmyk(100, 53, 0, 28)

Luminance 0.1028

Contrast Black 3.06:1White 6.87:1

CSS

--color-0057b8: #0057B8;
.background-0057b8 { background-color: #0057B8; }
.text-0057b8 { color: #0057B8; }

HEX meaning and use

About #0057B8

#0057B8 is classified as a cool blue value with vibrant and jewel tone visual character. #0057B8 is visually closest to Signal Blue, a named blue color with HEX #0057B8.

The RGB channels are 0, 87, and 184, with blue carrying the strongest channel weight. In HSL, the hue is 212deg with 100% saturation and 36% lightness, so this page treats it as a high-saturation, mid-lightness atlas color rather than a generic swatch.

Practical uses for this HEX value include color conversion, WCAG contrast checks, CSS color tokens, and rich accent palettes. Its luminance is 0.1028, white 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 text3.06:1AA Fail

White text6.87:1AA Pass

AA text options: #FFFFFF, #F5F5F5.

AAA text options: none in seed set.

Accessibility-Safe Pairings and Alternatives

Use these pairings when #0057B8 needs readable text, badges, interface states, or nearby accessible alternatives.

Black text#0000003.06:1 · Fail

White text#FFFFFF6.87:1 · AA

Accessible Alternatives

#002B5C#002B5C · #FFFFFF text · best 14:1 #0600B8#0600B8 · #FFFFFF text · best 12.35:1 Cobalt Blue#0047AB · #FFFFFF text · best 8.43:1 #00B1B8#00B1B8 · #000000 text · best 7.98:1 #1457A3#1457A3 · #FFFFFF text · best 7.19:1

Generated Palette

Signal Blue#0057B8

#B86200#B86200

#00B1B8#00B1B8

#0600B8#0600B8

#1482FF#1482FF

#002B5C#002B5C

Color Harmonies

#B86200#B86200

#00B1B8#00B1B8

#0600B8#0600B8

#B80056#B80056

#56B800#56B800

Variants

#1482FF#1482FF

#002B5C#002B5C

#0056B8#0056B8

#1457A3#1457A3

#4796F0#4796F0

#0069E0#0069E0

Nearest Named Colors

Signal Blue#0057B8

Sapphire#0F52BA

Cobalt Blue#0047AB

Denim#1560BD

Safety Blue#0067A5

Luminance0.1028

Black text3.06:1AA Fail

White text6.87:1AA 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":"#0057B8","rgb":[0,87,184],"hsl":[212,100,36],"cmyk":[100,53,0,28],"luminance":0.1028,"contrast":{"black":3.06,"white":6.87}}

WCAG

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

Safe pairings

[{"name":"Black text","hex":"#000000","contrast":3.06,"wcagAA":false,"wcagAAA":false},{"name":"White text","hex":"#FFFFFF","contrast":6.87,"wcagAA":true,"wcagAAA":false}]

Accessible alternatives

[{"name":"#002B5C","hex":"#002B5C","family":"blue","bestTextColor":"#FFFFFF","contrastBlack":1.5,"contrastWhite":14,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF","#F5F5F5"]},{"name":"#0600B8","hex":"#0600B8","family":"blue","bestTextColor":"#FFFFFF","contrastBlack":1.7,"contrastWhite":12.35,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF","#F5F5F5"]},{"name":"Cobalt Blue","hex":"#0047AB","family":"blue","bestTextColor":"#FFFFFF","contrastBlack":2.49,"contrastWhite":8.43,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF","#F5F5F5"]},{"name":"#00B1B8","hex":"#00B1B8","family":"cyan","bestTextColor":"#000000","contrastBlack":7.98,"contrastWhite":2.63,"wcagAA":["#000000","#1A1A1A"],"wcagAAA":["#000000"]},{"name":"#1457A3","hex":"#1457A3","family":"blue","bestTextColor":"#FFFFFF","contrastBlack":2.92,"contrastWhite":7.19,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF"]}]

AI context

{"semanticGroups":["cool blue","vibrant","jewel tone","vibrant blue","jewel tone blue","Signal Blue adjacent"],"useCases":["color conversion","WCAG contrast checks","CSS color tokens","rich accent palettes","high-energy accents","calm digital interfaces"],"contrastSafeWith":["#FFFFFF","#F5F5F5"],"relatedEndpoints":["https://www.colorsencyclopedia.com/api/hex/0057b8.json","https://www.colorsencyclopedia.com/api/hex.json","https://www.colorsencyclopedia.com/api/colors/signal-blue.json","https://www.colorsencyclopedia.com/api/colors/sapphire.json","https://www.colorsencyclopedia.com/api/colors/cobalt-blue.json"]}

Harmonies

{"complementary":"#B86200","analogous":["#00B1B8","#0600B8"],"triadic":["#B80056","#56B800"],"tetradic":["#B800B1","#B86200","#00B806"],"splitComplementary":["#B80600","#B1B800"],"monochromatic":["#1482FF","#0057B8","#002B5C"]}

Variants

{"light":"#1482FF","dark":"#002B5C","saturated":"#0056B8","desaturated":"#1457A3","pastel":"#4796F0","neon":"#0069E0"}

Nearest named colors

[{"slug":"signal-blue","name":"Signal Blue","hex":"#0057B8","distance":0},{"slug":"sapphire","name":"Sapphire","hex":"#0F52BA","distance":15.937377450509228},{"slug":"cobalt-blue","name":"Cobalt Blue","hex":"#0047AB","distance":20.615528128088304},{"slug":"denim","name":"Denim","hex":"#1560BD","distance":23.388031127053},{"slug":"safety-blue","name":"Safety Blue","hex":"#0067A5","distance":24.839484696748443}]

#0057B8

CSS

About #0057B8

WCAG Accessibility

Accessibility-Safe Pairings and Alternatives

Accessible Alternatives

Generated Palette

Color Harmonies

Variants

Nearest Named Colors

Machine-Readable HEX Data (JSON)

Related HEX Guides