HEX atlas value

#003399

#003399 is a cool blue HEX color nearest Smalt. RGB 0, 51, 153, HSL 220° 100% 30%, luminance 0.0467; view contrast and conversions.

blue cool jewel-tone

#003399 Sample readable text

HEX #003399

RGB rgb(0, 51, 153)

HSL hsl(220 100% 30%)

CMYK cmyk(100, 67, 0, 40)

Luminance 0.0467

Contrast Black 1.93:1White 10.86:1

CSS

--color-003399: #003399;
.background-003399 { background-color: #003399; }
.text-003399 { color: #003399; }

HEX meaning and use

About #003399

#003399 is classified as a cool blue value with jewel tone visual character. #003399 is visually closest to Smalt, a named blue color with HEX #003399.

The RGB channels are 0, 51, and 153, with blue carrying the strongest channel weight. In HSL, the hue is 220deg with 100% saturation and 30% lightness, so this page treats it as a high-saturation, dark 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 0.0467, 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 text1.93:1AA Fail

White text10.86:1AA Pass

AA text options: #FFFFFF, #F5F5F5.

AAA text options: #FFFFFF, #F5F5F5.

Accessibility-Safe Pairings and Alternatives

Use these pairings when #003399 needs readable text, badges, interface states, or nearby accessible alternatives.

Black text#0000001.93:1 · Fail

White text#FFFFFF10.86:1 · AAA

Accessible Alternatives

#00143D#00143D · #FFFFFF text · best 17.98:1 #190099#190099 · #FFFFFF text · best 13.98:1 Zaffre#0014A8 · #FFFFFF text · best 12.61:1 #113988#113988 · #FFFFFF text · best 10.69:1 Egyptian Blue#1034A6 · #FFFFFF text · best 10.17:1

Generated Palette

Smalt#003399

#996600#996600

#007F99#007F99

#190099#190099

#0052F5#0052F5

#00143D#00143D

Color Harmonies

#996600#996600

#007F99#007F99

#190099#190099

#990033#990033

#339900#339900

Variants

#0052F5#0052F5

#00143D#00143D

Smalt#003399

#113988#113988

#2B6CEE#2B6CEE

#0041C2#0041C2

Nearest Named Colors

Smalt#003399

Egyptian Blue#1034A6

Cobalt Blue#0047AB

Zaffre#0014A8

Persian Blue#1C39BB

Luminance0.0467

Black text1.93:1AA Fail

White text10.86:1AA 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":"#003399","rgb":[0,51,153],"hsl":[220,100,30],"cmyk":[100,67,0,40],"luminance":0.0467,"contrast":{"black":1.93,"white":10.86}}

WCAG

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

Safe pairings

[{"name":"Black text","hex":"#000000","contrast":1.93,"wcagAA":false,"wcagAAA":false},{"name":"White text","hex":"#FFFFFF","contrast":10.86,"wcagAA":true,"wcagAAA":true}]

Accessible alternatives

[{"name":"#00143D","hex":"#00143D","family":"blue","bestTextColor":"#FFFFFF","contrastBlack":1.17,"contrastWhite":17.98,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF","#F5F5F5"]},{"name":"#190099","hex":"#190099","family":"blue","bestTextColor":"#FFFFFF","contrastBlack":1.5,"contrastWhite":13.98,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF","#F5F5F5"]},{"name":"Zaffre","hex":"#0014A8","family":"blue","bestTextColor":"#FFFFFF","contrastBlack":1.67,"contrastWhite":12.61,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF","#F5F5F5"]},{"name":"#113988","hex":"#113988","family":"blue","bestTextColor":"#FFFFFF","contrastBlack":1.96,"contrastWhite":10.69,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF","#F5F5F5"]},{"name":"Egyptian Blue","hex":"#1034A6","family":"blue","bestTextColor":"#FFFFFF","contrastBlack":2.06,"contrastWhite":10.17,"wcagAA":["#FFFFFF","#F5F5F5"],"wcagAAA":["#FFFFFF","#F5F5F5"]}]

AI context

{"semanticGroups":["cool blue","jewel tone","jewel tone blue","Smalt adjacent"],"useCases":["color conversion","WCAG contrast checks","CSS color tokens","rich accent palettes","calm digital interfaces"],"contrastSafeWith":["#FFFFFF","#F5F5F5"],"relatedEndpoints":["https://www.colorsencyclopedia.com/api/hex/003399.json","https://www.colorsencyclopedia.com/api/hex.json","https://www.colorsencyclopedia.com/api/colors/smalt.json","https://www.colorsencyclopedia.com/api/colors/egyptian-blue.json","https://www.colorsencyclopedia.com/api/colors/cobalt-blue.json"]}

Harmonies

{"complementary":"#996600","analogous":["#007F99","#190099"],"triadic":["#990033","#339900"],"tetradic":["#99007F","#996600","#00991A"],"splitComplementary":["#991900","#7F9900"],"monochromatic":["#0052F5","#003399","#00143D"]}

Variants

{"light":"#0052F5","dark":"#00143D","saturated":"#003399","desaturated":"#113988","pastel":"#2B6CEE","neon":"#0041C2"}

Nearest named colors

[{"slug":"smalt","name":"Smalt","hex":"#003399","distance":0},{"slug":"egyptian-blue","name":"Egyptian Blue","hex":"#1034A6","distance":20.639767440550294},{"slug":"cobalt-blue","name":"Cobalt Blue","hex":"#0047AB","distance":26.90724809414742},{"slug":"zaffre","name":"Zaffre","hex":"#0014A8","distance":34.438350715445125},{"slug":"persian-blue","name":"Persian Blue","hex":"#1C39BB","distance":44.45222154178574}]

#003399

CSS

About #003399

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