Ultramarine (#3F00FF)

The hex code for Ultramarine is #3F00FF. It is rgb(63, 0, 255) in RGB, hsl(255, 100%, 50%) in HSL, and about cmyk(75%, 100%, 0%, 0%) in CMYK — a mid-tone purple. White text is the more readable choice on this background.

#3F00FF

HEX#3F00FF

RGBrgb(63, 0, 255)

HSLhsl(255, 100%, 50%)

HSVhsv(255, 100%, 100%)

CMYKcmyk(75%, 100%, 0%, 0%)

OKLCHoklch(47.3% 0.301 273.6)

LABlab(32.19% 69.75 -107.58)

LCHlch(32.19% 128.21 302.96)

Colors Closest to Ultramarine

Ultramarine is a registered color name. These are the named colors nearest to it, measured as CIE76 distance in CIELAB — a perceptual scale, so the ordering matches what the eye sees rather than how close the raw RGB numbers happen to sit.

Indigo (Color Wheel)#4000FFΔE 0.16 Blue#0000FFΔE 5.37 Han Purple#5218FAΔE 8.35 Ultramarine Blue(caran D'ache)#2111EFΔE 8.91 Electric Indigo#6F00FFΔE 10.24 Poison Purple#7F01FEΔE 14.93

Browse the full index of named colors A-Z or every purple in the library.

#3F00FF Channel Values

How Ultramarine breaks down in each color model. Hue is measured in degrees around the color wheel; saturation, lightness, and the CMYK inks are percentages.

Model	Channels	Notes
RGB	R 63 · G 0 · B 255	8-bit channels as sent to the display
HSL	H 255° · S 100% · L 50%	Easiest model for building lighter and darker variants
HSV	H 255° · S 100% · V 100%	Matches the picker in most design tools
CMYK	C 75% · M 100% · Y 0% · K 0%	Approximate ink mix; confirm with an ICC profile before printing
Luminance	7.91:1 vs white · 2.66:1 vs black	WCAG 2.2 relative-luminance contrast ratios

Text Contrast & Accessibility

WCAG 2.2 contrast ratios for text on a Ultramarine background. AA requires 4.5:1 for normal text and 3:1 for large text; AAA requires 7:1. Contrast is one check, not a full accessibility review.

TextWhite text7.91:1AA normal ✓AA large ✓AAA normal ✓

TextBlack text2.66:1AA normal ✗AA large ✗AAA normal ✗

Need a specific ratio against another background? Open #3F00FF in the contrast checker.

Colors That Go With Ultramarine

Pairings derived from color-wheel relationships. The complementary color sits opposite Ultramarine; analogous colors sit beside it; triadic and split-complementary sets spread evenly around the wheel. Select any swatch for its own breakdown.

Base

Complementary

Analogous

Analogous

Triadic

Triadic

Split comp.

Split comp.

Tints & Shades of Ultramarine

Lighter tints and darker shades built by moving the lightness channel while holding hue and saturation, which is what you want for hover states, backgrounds, and text variants.

Tints

Shades

Want a full 50-950 ramp with semantic roles? Generate design tokens from #3F00FF.

How Ultramarine Looks with Color Vision Deficiency

Simulated with the Viénot, Brettel & Mollon LMS projection model. Anomalous types are rendered as partial versions of the matching dichromacy, which is an approximation rather than a per-person clinical model.

Typical#3F00FF

Protanopia#1717FF

Protanomaly#2C10FF

Deuteranopia#2323FF

Deuteranomaly#3019FF

Tritanopia#006363

Tritanomaly#004EB7

Achromatopsia#515151

Test a full palette in the color blindness simulator.

Using #3F00FF in Code

Copy-ready declarations for the places this color usually ends up.

CSS custom property--ultramarine: #3F00FF;

CSS backgroundbackground-color: #3F00FF;

Tailwind configcolors: { 'ultramarine': '#3F00FF' }

SwiftUIColor(red: 0.247, green: 0.000, blue: 1.000)

Android XML<color name="ultramarine">#3F00FF</color>

SVG fillfill="#3F00FF"

More Purple Colors

Ultramarine sits in the purplefamily. These are its neighbours across that family's full range, each with its own breakdown.

4000ff 3d1f7a 402060 3c0366 410070 390061 410f70 36004d 42144d 341146 470066 3300cc 512888 6231c4 6f00ff 842bb1 967bb6 9f00ff af95e4 c27aff cfb6e7 e3a3ff fdf4ff 2f0b51

#3F00FF Frequently Asked Questions

What is the hex code for Ultramarine?

The hex code for Ultramarine is #3F00FF. That is rgb(63, 0, 255) in RGB, hsl(255, 100%, 50%) in HSL, and approximately cmyk(75%, 100%, 0%, 0%) in CMYK.

What is the RGB value of #3F00FF?

#3F00FF is rgb(63, 0, 255) — red 63, green 0, and blue 255 on the 0-255 scale.

What is the CMYK value of #3F00FF?

#3F00FF converts to approximately cmyk(75%, 100%, 0%, 0%). CMYK output is a mathematical approximation for planning; confirm production print colors with your printer and ICC profile.

Should text on #3F00FF be black or white?

White text is the more readable choice. #3F00FF scores 7.91:1 against white and 2.66:1 against black, and WCAG 2.2 asks for at least 4.5:1 for normal body text.

Can I write #3F00FF as a CSS color keyword?

No. #3F00FF is not one of the CSS color keywords, so it has to be written as a hex, rgb() or hsl() value. The closest keyword is blue (#0000FF) at a CIE76 distance of 5.37, which is clearly related but distinguishable side by side.

Open Ultramarine in a Tool

Hex to RGB Hex to HSL Hex to CMYK Hex to OKLCH Hex to Pantone Build a palette Make a gradient

Keep exploring: every purple in the color library, the guide to shades of purple, or the full color library.