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violet · cool

#331b75

a dark, vivid violet · cool · closest name: Midnight Blue

Token name suggestion: Shadow Plum

RGB
51, 27, 117
HSL
256°, 63%, 28%
CMYK
56, 77, 0, 54
Luminance
0.0277

#331b75 is a dark vivid violet, 256° on the wheel and 74/100 on the cool side. Put white text on it (13.51:1). As text it scores 13.51:1 on white — safe at any size. Nearest name is Midnight Blue, nearest Tailwind family is slate.

hsl(256 63% 28%)rgb(51 27 117)Base step 800AAA inkCool

At a glance

Every number on this page in one read: what #331b75 is made of, how bright it looks, and which way it leans.

Hex
#331b75
Hue
256°
violet
Saturation
63%
vivid
Lightness
28%
dark
Brightness
46%
HSV value
Perceived
21%
weighted brightness
Luminance
0.0277
WCAG relative
Temperature
Cool
74/100 cool
Color family
Violet
Tone
Vivid
Best ink
White
13.51:1
Closest name
Midnight Blue
ΔE2000 3.7
Chroma
59.3
LCH, 0–130ish
OKLCH L
0.319
perceptual lightness
Tailwind
slate
500 · ΔE 27
Web-safe
#333366
nearest of 216
Where it sits
Hue256° of 360°
Saturation63%
Lightness28%
Saturation × lightness field

Left edge is grey, right edge is full chroma; top is white, bottom is black. The dot is #331b75.

Temperature
Warm ← → Cool74% cool

Reads cool. Warm and cool siblings keep the same lightness, so you can swap one in without redoing your contrast maths.

Luminance by channel
Red25%
Green28%
Blue46%

Green carries most of what the eye calls brightness — that is why WCAG weights it 0.7152.

Every format

HEX#331b75
HEX (8-digit)#331b75ff
RGBrgb(51, 27, 117)
RGBArgba(51, 27, 117, 1)
HSLhsl(256, 63%, 28%)
HSV / HSBhsv(256, 77%, 46%)
HWBhwb(256 11% 54%)
CMYKcmyk(56%, 77%, 0%, 54%)
LABlab(19.1 35.6 -47.4)
LCHlch(19.1 59.3 306.9)
OKLCHoklch(0.319 0.143 287.5)
XYZ (D65)xyz(4.97, 2.77, 17.10)
Decimal3349365
Display P3color(display-p3 0.200 0.106 0.459)
Web-safe#333366

Copy-ready code

every platformclick to select
/* CSS */
color: #331b75;
background-color: #331b75;
/* CSS custom property */
--brand: #331b75;
/* Tailwind (arbitrary) */
class="text-[#331b75] bg-[#331b75]"
/* SCSS */
$brand: #331b75;
/* SwiftUI */
Color(red: 0.200, green: 0.106, blue: 0.459)
/* UIKit */
UIColor(red: 0.200, green: 0.106, blue: 0.459, alpha: 1)
/* Android XML */
<color name="brand">#331B75</color>
/* Android Compose */
Color(0xFF331B75)
/* Flutter */
Color(0xFF331B75)
/* Python / OpenCV (BGR) */
(117, 27, 51)
/* Python / PIL (RGB) */
(51, 27, 117)
/* Java AWT */
new Color(51, 27, 117)
/* .NET */
Color.FromArgb(255, 51, 27, 117)
/* OpenGL / Unity (0–1) */
(0.2000f, 0.1059f, 0.4588f, 1f)
/* LaTeX */
\definecolor{brand}{RGB}{51,27,117}
modern cssclick to select
/* mix without leaving CSS */
background: color-mix(in oklab, #331b75 85%, white);
border-color: color-mix(in oklab, #331b75 40%, transparent);
/* theme-aware in one line */
color: light-dark(#2D1868, #DAD3EE);
/* relative colour syntax */
--hover: hsl(from #331b75 h s calc(l - 7));

Design tokens

The same ramp in the four formats a team actually needs. Paste one and the whole palette lands with it.

css custom propertiesclick to select
:root {
  --brand-50: #F6F4FB;
  --brand-100: #ECE8F7;
  --brand-200: #D5CCF0;
  --brand-300: #B7A4EA;
  --brand-400: #9276DF;
  --brand-500: #6E49D5;
  --brand-600: #572EC7;
  --brand-700: #4826A6;
  --brand-800: #331b75;
  --brand-900: #2D1A60;
  --brand-950: #1C103C;
  --brand: #331b75;
  --brand-ink: #ffffff;
  --brand-surface: #F6F4FA;
  --brand-border: #CCC0ED;
  --brand-hover: #261458;
  --brand-pressed: #1A0E3B;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand-surface: #181424;
    --brand-ink: #DAD3EE;
  }
}
tailwind.config.jsclick to select
theme: {
  extend: {
    colors: {
      brand: {
        50: '#F6F4FB',
        100: '#ECE8F7',
        200: '#D5CCF0',
        300: '#B7A4EA',
        400: '#9276DF',
        500: '#6E49D5',
        600: '#572EC7',
        700: '#4826A6',
        800: '#331b75',
        900: '#2D1A60',
        950: '#1C103C',
        DEFAULT: '#331b75',
      },
    },
  },
}
scss mapclick to select
$brand: (
  '50': #F6F4FB,
  '100': #ECE8F7,
  '200': #D5CCF0,
  '300': #B7A4EA,
  '400': #9276DF,
  '500': #6E49D5,
  '600': #572EC7,
  '700': #4826A6,
  '800': #331b75,
  '900': #2D1A60,
  '950': #1C103C,
);
$brand-base: #331b75;
$brand-ink: #ffffff;

@function brand($step) { @return map-get($brand, $step); }
w3c design tokens (json)click to select
{
  "color": {
    "brand": {
      "50": { "$value": "#F6F4FB", "$type": "color" },
      "100": { "$value": "#ECE8F7", "$type": "color" },
      "200": { "$value": "#D5CCF0", "$type": "color" },
      "300": { "$value": "#B7A4EA", "$type": "color" },
      "400": { "$value": "#9276DF", "$type": "color" },
      "500": { "$value": "#6E49D5", "$type": "color" },
      "600": { "$value": "#572EC7", "$type": "color" },
      "700": { "$value": "#4826A6", "$type": "color" },
      "800": { "$value": "#331b75", "$type": "color" },
      "900": { "$value": "#2D1A60", "$type": "color" },
      "950": { "$value": "#1C103C", "$type": "color" }
    },
    "brandInk": { "$value": "#ffffff", "$type": "color" }
  }
}

Best text color

Only one of black and white can be right. This is the one, with the number that proves it.

Readable at a glance#ffffff on #331b75 · 13.51:1
Use #ffffffAAA at every size.
Aa
12px
Aa
16px
Aa
24px
Aa
White text · 13.51:1 · recommended
AA pass · AA large pass · AAA pass
Aa
Black text · 1.55:1
AA fail · AA large fail · AAA fail
Reading the other direction: #331b75 as text scores 13.51:1 on white and 1.55:1 on black.
Best tinted ink on it, if plain black or white feels flat: #EFEAFA at 11.46:1.

Make it accessible

A contrast checker tells you that you failed. This tells you what to ship instead — same hue, same saturation, lightness moved only as far as WCAG demands.

The quick fox
#331b75 · 13.51:1
AA on whitealready passes
#331b75
The quick fox
#331b75 · 13.51:1
AAA on whitealready passes
#331b75
The quick fox
#7F5EDA · 4.52:1
AA on black+33% L
#7F5EDA
The quick fox
#A088E3 · 7.13:1
AAA on black+43% L
#A088E3

Large text — 24px regular or 18.66px bold and above — only needs 3:1, so #331B75 is enough for headings on white. Non-text elements such as icons, chart strokes and focus rings also sit at 3:1 under WCAG 2.2 (1.4.11).

Accessibility — WCAG contrast

Aa
#331b75 on white: 13.51:1
AA ✓ pass · AA-large · AAA
Aa
#331b75 on black: 1.55:1
AA ✗ fail · AA-large · AAA
Against the neutral ladder

Contrast is symmetric, so each row covers both directions: #331b75 as text on that neutral, and that neutral as text on #331b75.

NeutralRatioBoth directions
White13.51:1AaAa
Slate 5012.91:1AaAa
Slate 10012.33:1AaAa
Slate 20010.96:1AaAa
Slate 3009.10:1AaAa
Slate 4005.27:1AaAa
Slate 5002.84:1AaAa
Slate 6001.78:1AaAa
Slate 7001.30:1AaAa
Slate 8001.08:1AaAa
Slate 9001.32:1AaAa
Black1.55:1AaAa
Colour vision deficiency
true color
protanopia · #003078
deuteranopia · #002C73
tritanopia · #183446

Roughly one man in twelve has some form of colour vision deficiency. If any of the three panels above is hard to tell apart from a neighbouring colour in your palette, add a shape, an icon or a label so the meaning does not rest on hue alone.

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #331b75 is pinned to step 800; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F6F4FB
#ECE8F7
#D5CCF0
#B7A4EA
#9276DF
#6E49D5
#572EC7
#4826A6
#331b75
#2D1A60
#1C103C
Base = 800Lightest = 50 · #F6F4FBDarkest = 950 · #1C103CText step on white = 500
Perceptual ramp — OKLCH

The same eleven steps expressed in OKLCH, where equal lightness numbers actually look equally spaced. HSL ramps go muddy in the yellows and washed out in the blues; this one does not. Modern browsers render it natively — the hex ramp above is the fallback.

50100200300400500600700800900950
oklch tokensclick to select
:root {
  --brand-50: oklch(0.97 0.036 287.5);
  --brand-100: oklch(0.94 0.057 287.5);
  --brand-200: oklch(0.88 0.086 287.5);
  --brand-300: oklch(0.80 0.111 287.5);
  --brand-400: oklch(0.72 0.131 287.5);
  --brand-500: oklch(0.64 0.143 287.5);
  --brand-600: oklch(0.56 0.143 287.5);
  --brand-700: oklch(0.48 0.134 287.5);
  --brand-800: oklch(0.40 0.120 287.5);
  --brand-900: oklch(0.32 0.100 287.5);
  --brand-950: oklch(0.24 0.079 287.5);
}

Colors that work with #331b75

Not a palette — a role sheet. Each swatch answers one question you will hit while building the component.

Text on it#ffffff
White wins here
Surface#F6F4FA
Tinted page background
Border#CCC0ED
Hairlines and dividers
Muted text#604B9B
Captions on the surface
Accent#767818
Second voice, not a rival
Dark variant#2D1868
Hover, pressed, headers
Light variant#EFEAFA
Selected rows, tints
Dark surface#181424
Dark-mode background
Hover#261458
One step down in lightness
Pressed#1A0E3B
Two steps down
Disabled#73649C
Chroma pulled out
Focus ring#36178E
Offset from the fill so it reads
Light mode
Everything in its place

Surface, border, heading and body all derive from this one hue, so the screen stays coherent without a second palette.

Primary actionSecondaryBadge
Dark mode
Same hue, inverted

Lightness flips, hue holds. The accent stays the anchor in both themes.

Primary actionSecondaryAccent

In real components

The same eight roles, wired into the interface patterns you will actually build with them. Every state below is a computed value, not a mock-up.

Buttons and states
Save changesHoverPressedDisabled
OutlineSubtleLinkFocused
Form field
you@company.com

Focus ring uses the light variant so the field still reads as one shape.

Send me product updates
Notice
Your export is ready

The file stays available for seven days. Download it before it expires.

NewBetaDraft
Data
Storage used68%
Acme LtdActive
NorthwindTrial
GlobexActive

How to use #331b75

Derived from its contrast, chroma and lightness — not from taste.

Works well for
  • Body text and links on white
  • Primary buttons and calls to action
  • Focus rings, active and selected states
  • Headers, footers and dark-mode surfaces
  • Brand accents, badges and data highlights
Use with care
  • Text on black or near-black surfaces
  • Full-page backgrounds — tiring over long sessions
  • Black text placed on it
  • Pairing with a same-lightness hue — edges vibrate
Minimum size as text on white
Any size
Safe as a fill behind white type
Yes
Safe as a 1px border on white
Yes

Meaning and mood

What a colour in this family tends to signal, and how this particular chroma and lightness change the reading.

creativepremiummodernimaginative

Violet sits between the warmth of red and the calm of blue, so it reads as inventive without reading as risky. Current shorthand for software craft.

This is a confident chroma: strong enough to lead a brand, restrained enough to live in an interface all day. The low lightness adds weight and formality.

Worth knowing

Deep violets swallow detail on screens with poor gamma; check it on a cheap laptop panel.

Reads as
  • FormalityHigh
  • EnergyMedium-high
  • Weight72/100
  • TemperatureCool
  • ApproachabilityReserved

Colour associations are cultural and vary by market. Treat these as a starting point for a conversation with your audience, not a finding about them.

Similar colors

One move away from this hex in each direction. Every swatch is its own page.

Color relationships

The wheel positions with their names attached, so you can grab the one you actually need.

Complementary#5D751B
Analogous left#1B3075
Analogous right#601B75
Split-complement 1#75601B
Split-complement 2#30751B
Triadic 1#75331B
Triadic 2#1B7533
Tetradic#751B30
On the wheel
Base+30°−30°+120°+240°+180°256°

#331b75 sits at 256°. Every dot is a harmony position and links to its own page in the table alongside.

RGB percentages

Red20.0%
Green10.6%
Blue45.9%
R · 0–255
51
0x33
G · 0–255
27
0x1b
B · 0–255
117
0x75

CMYK percentages

Cyan56.4%
Magenta76.9%
Yellow0.0%
Key (black)54.1%

Total ink coverage is 187%. Most commercial presses cap around 300% — above that, sheets stop drying properly.

Color previews

#331b75 text on a black background

contrast 1.55:1

Card sample

#331b75 text on a white background

contrast 13.51:1

Card sample

#331b75 on grey

12.33:1

#331b75 on its own surface

12.38:1

#331b75 on its dark surface

1.33:1

CSS3 live lab

Text font color

The quick brown fox

color: #331b75;
Background color
Panel with #331b75 background
background-color: #331b75;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #331b75;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(51, 27, 117, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(51, 27, 117, 0.45);
Border & gradient
Gradient panel
border: 3px solid #331b75;
background: linear-gradient(135deg, #331b75, #6F1B75);
Gradient text

Gradient headline

background: linear-gradient(90deg, #331b75, #751B64);
-webkit-background-clip: text;
color: transparent;
Focus ring
Focused control
outline: 2px solid #331b75;
outline-offset: 3px;
Underline & caret

Marked up text

text-decoration-color: #331b75;
caret-color: #331b75;
Left rule
Pull quote or callout
border-left: 4px solid #331b75;
Ring + tint
Selected chip
background: #EFEAFA;
box-shadow: inset 0 0 0 2px #331b75;
Conic badge
68%
background: conic-gradient(#331b75 68%, #e2e8f0 0);

Transparency

What each alpha value actually composites to. The top row is #331b75 over white; the bottom row is the same alpha over a checkerboard, so you can see what survives on a photo or a video.

Bottom row of hexes is the flattened result over white — use those when a design tool refuses transparency, or when you need a solid fallback.

alpha in every syntaxclick to select
rgba(51, 27, 117, 0.5)
rgb(51 27 117 / 50%)
#331b7580
hsl(256 63% 28% / 50%)
color-mix(in srgb, #331b75 50%, transparent)
Alpha8-digit hexFlat on white
10%#331b751a#EBE8F1
20%#331b7533#D6D1E3
40%#331b7566#ADA4C8
60%#331b7599#8576AC
80%#331b75cc#5C4991

Gradients from #331b75

Six recipes, each built from this hex and shown with the exact CSS that produced it.

Elevation
Same hue, three lightnesses — safe anywhere
background: linear-gradient(135deg, #4926A7, #331b75 45%, #2D1868);
Duotone
A short hue run reads richer than a flat fill
background: linear-gradient(120deg, #331b75, #5C155B);
Complement sweep
Loud — keep it behind large type only
background: linear-gradient(90deg, #331b75, #5D751B);
Spotlight
Hero panels and app headers
background: radial-gradient(120% 120% at 20% 0%, #532CBF 0%, #331b75 45%, #2D1868 100%);
Soft wash
Section backgrounds that stay readable
background: linear-gradient(180deg, #F6F4FA, #ffffff);
Mesh
Ambient background, no image weight
background: radial-gradient(60% 60% at 15% 20%, #254B9E 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #7D218E 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #2D1868 0%, transparent 65%), #331b75;

Monochromatic scale

Palettes built from #331b75

Shades — darker

Tints — lighter

Tones — desaturated

Color harmonies

Nearest named colors

Ranked with CIEDE2000 across all 139 CSS keywords. Under ΔE 2 the eye stops telling them apart; over ΔE 10 they are plainly different colors.

#331b75 in the real world

Where a color in this family tends to land, and the interface roles it is usually asked to play.

Industries
Creative toolsFintechBeautyLuxury
Common UI roles
ButtonsLinksFocus statesCharts
Print note

Converts to four-color process without much drama. Proof it anyway.

On screens

Very dark values collapse into each other on cheap panels — leave more lightness between your darkest steps than the numbers suggest.

In dark mode

Too dim on dark surfaces at 1.55:1 — lift it to #7F5EDA for body text, or reserve it for fills.

Explore nearby colors

Small, deliberate steps away from this hex — useful when you are hunting for the version of a colour that finally feels right.

#331b75, answered

What color is #331b75?

#331b75 is a dark vivid violet, closest to Midnight Blue (ΔE2000 3.7). It sits at 256° on the hue wheel with 63% saturation and 28% lightness, which reads as cool.

What is the RGB value of #331b75?

rgb(51, 27, 117) — 51 red, 27 green and 117 blue out of 255, or 20% / 10.6% / 45.9% by channel.

What is #331b75 in HSL and HSV?

hsl(256, 63%, 28%) and hsv(256, 77%, 46%). HSL is what CSS takes; HSV is what your design tool's picker shows, which is why the saturation numbers rarely match.

Is #331b75 a light or a dark color?

It is a dark color. Relative luminance is 0.0277 and perceived brightness is 21%, so white text on it reaches 13.51:1.

Should I use black or white text on #331b75?

White. It scores 13.51:1 against #331b75, versus 1.55:1 for black — AAA at any size.

Is #331b75 accessible on a white background?

#331b75 on white scores 13.51:1, which clears AAA at every size.

What is the complementary color of #331b75?

#5D751B sits directly opposite on the wheel. Softer options are the split-complements #75601B and #30751B, which give the same contrast with far less vibration.

What colors go well with #331b75?

For interface work: #F6F4FA as the surface, #CCC0ED for borders, #604B9B for secondary text, #767818 as an accent and #2D1868 for hover and pressed states. For a palette, the analogous pair #1B3075 and #601B75 stays calm, while #5D751B is the loudest partner.

What is #331b75 in CMYK for printing?

cmyk(56%, 77%, 0%, 54%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #331b75 warm or cool?

Cool — it scores 74 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #541B75; nudged cooler, #1A2376.

Which Tailwind color is closest to #331b75?

The slate family — its 500 step is #64748b, ΔE2000 27 away. That is a visible difference, so define #331b75 as a custom token rather than reaching for the built-in.

How do I use #331b75 in Tailwind CSS?

Inline it as an arbitrary value with bg-[#331b75] or text-[#331b75], or register the whole ramp under theme.extend.colors.brand so you get bg-brand-500 and friends. The generated 50–950 scale on this page is ready to paste into your config.

What is #331b75 with 50% opacity?

rgba(51, 27, 117, 0.5), or #331b7580 in eight-digit hex. Over white that composites to #998DBA; over black, #1A0E3B.

Is #331b75 a web-safe color?

No. The nearest web-safe colour is #333366, ΔE2000 9.1 away. The palette only matters for legacy displays and some email clients now.

What does the color #331b75 mean?

As a violet, it reads creative, premium, modern. Violet sits between the warmth of red and the calm of blue, so it reads as inventive without reading as risky. Current shorthand for software craft. At this chroma the effect is amplified — it will dominate whatever sits beside it.

What gradient works with #331b75?

The safest is same-hue elevation: linear-gradient(135deg, #4926A7, #331b75 45%, #2D1868). For more colour, a short hue run to #5C155B keeps it rich without turning muddy.

Work with #331b75 in the Color Lab

Every tool opens with this colour already loaded.

Every value on this page is computed from #331b75 at request time — conversions, contrast ratios and ΔE distances are calculated, never looked up.