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violet · cool

#423751

a dark, soft violet · cool · closest name: Dark Slate Blue

Token name suggestion: Shadow Plum

RGB
66, 55, 81
HSL
265°, 19%, 27%
CMYK
19, 32, 0, 68
Luminance
0.0448

#423751 is a dark soft violet, 265° on the wheel and 60/100 on the cool side. Put white text on it (11.07:1). As text it scores 11.07:1 on white — safe at any size. Nearest name is Dark Slate Blue, nearest Tailwind family is zinc.

hsl(265 19% 27%)rgb(66 55 81)Base step 900AAA inkCool

At a glance

Every number on this page in one read: what #423751 is made of, how bright it looks, and which way it leans.

Hex
#423751
Hue
265°
violet
Saturation
19%
soft
Lightness
27%
dark
Brightness
32%
HSV value
Perceived
24%
weighted brightness
Luminance
0.0448
WCAG relative
Temperature
Cool
60/100 cool
Color family
Violet
Tone
Soft
Best ink
White
11.07:1
Closest name
Dark Slate Blue
ΔE2000 14.1
Chroma
17.8
LCH, 0–130ish
OKLCH L
0.359
perceptual lightness
Tailwind
zinc
500 · ΔE 21.6
Web-safe
#333366
nearest of 216
Where it sits
Hue265° of 360°
Saturation19%
Lightness27%
Saturation × lightness field

Left edge is grey, right edge is full chroma; top is white, bottom is black. The dot is #423751.

Temperature
Warm ← → Cool60% 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
Red26%
Green61%
Blue13%

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

Every format

HEX#423751
HEX (8-digit)#423751ff
RGBrgb(66, 55, 81)
RGBArgba(66, 55, 81, 1)
HSLhsl(265, 19%, 27%)
HSV / HSBhsv(265, 32%, 32%)
HWBhwb(265 22% 68%)
CMYKcmyk(19%, 32%, 0%, 68%)
LABlab(25.2 10.9 -14.0)
LCHlch(25.2 17.8 307.9)
OKLCHoklch(0.359 0.046 303.5)
XYZ (D65)xyz(5.10, 4.48, 8.38)
Decimal4339537
Display P3color(display-p3 0.259 0.216 0.318)
Web-safe#333366

Copy-ready code

every platformclick to select
/* CSS */
color: #423751;
background-color: #423751;
/* CSS custom property */
--brand: #423751;
/* Tailwind (arbitrary) */
class="text-[#423751] bg-[#423751]"
/* SCSS */
$brand: #423751;
/* SwiftUI */
Color(red: 0.259, green: 0.216, blue: 0.318)
/* UIKit */
UIColor(red: 0.259, green: 0.216, blue: 0.318, alpha: 1)
/* Android XML */
<color name="brand">#423751</color>
/* Android Compose */
Color(0xFF423751)
/* Flutter */
Color(0xFF423751)
/* Python / OpenCV (BGR) */
(81, 55, 66)
/* Python / PIL (RGB) */
(66, 55, 81)
/* Java AWT */
new Color(66, 55, 81)
/* .NET */
Color.FromArgb(255, 66, 55, 81)
/* OpenGL / Unity (0–1) */
(0.2588f, 0.2157f, 0.3176f, 1f)
/* LaTeX */
\definecolor{brand}{RGB}{66,55,81}
modern cssclick to select
/* mix without leaving CSS */
background: color-mix(in oklab, #423751 85%, white);
border-color: color-mix(in oklab, #423751 40%, transparent);
/* theme-aware in one line */
color: light-dark(#3E344C, #E0DBE6);
/* relative colour syntax */
--hover: hsl(from #423751 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: #F7F6F8;
  --brand-100: #EFEDF2;
  --brand-200: #DDD8E3;
  --brand-300: #C5BCD2;
  --brand-400: #A89BBB;
  --brand-500: #8C79A4;
  --brand-600: #776392;
  --brand-700: #635379;
  --brand-800: #4F4261;
  --brand-900: #423751;
  --brand-950: #25202D;
  --brand: #423751;
  --brand-ink: #ffffff;
  --brand-surface: #F7F6F9;
  --brand-border: #D5CEDE;
  --brand-hover: #31293C;
  --brand-pressed: #1F1A27;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand-surface: #1B1721;
    --brand-ink: #E0DBE6;
  }
}
tailwind.config.jsclick to select
theme: {
  extend: {
    colors: {
      brand: {
        50: '#F7F6F8',
        100: '#EFEDF2',
        200: '#DDD8E3',
        300: '#C5BCD2',
        400: '#A89BBB',
        500: '#8C79A4',
        600: '#776392',
        700: '#635379',
        800: '#4F4261',
        900: '#423751',
        950: '#25202D',
        DEFAULT: '#423751',
      },
    },
  },
}
scss mapclick to select
$brand: (
  '50': #F7F6F8,
  '100': #EFEDF2,
  '200': #DDD8E3,
  '300': #C5BCD2,
  '400': #A89BBB,
  '500': #8C79A4,
  '600': #776392,
  '700': #635379,
  '800': #4F4261,
  '900': #423751,
  '950': #25202D,
);
$brand-base: #423751;
$brand-ink: #ffffff;

@function brand($step) { @return map-get($brand, $step); }
w3c design tokens (json)click to select
{
  "color": {
    "brand": {
      "50": { "$value": "#F7F6F8", "$type": "color" },
      "100": { "$value": "#EFEDF2", "$type": "color" },
      "200": { "$value": "#DDD8E3", "$type": "color" },
      "300": { "$value": "#C5BCD2", "$type": "color" },
      "400": { "$value": "#A89BBB", "$type": "color" },
      "500": { "$value": "#8C79A4", "$type": "color" },
      "600": { "$value": "#776392", "$type": "color" },
      "700": { "$value": "#635379", "$type": "color" },
      "800": { "$value": "#4F4261", "$type": "color" },
      "900": { "$value": "#423751", "$type": "color" },
      "950": { "$value": "#25202D", "$type": "color" }
    },
    "brandInk": { "$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 #423751 · 11.07:1
Use #ffffffAAA at every size.
Aa
12px
Aa
16px
Aa
24px
Aa
White text · 11.07:1 · recommended
AA pass · AA large pass · AAA pass
Aa
Black text · 1.90:1
AA fail · AA large fail · AAA fail
Reading the other direction: #423751 as text scores 11.07:1 on white and 1.90:1 on black.
Best tinted ink on it, if plain black or white feels flat: #F2F0F5 at 9.78:1.

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
#423751 · 11.07:1
AA on whitealready passes
#423751
The quick fox
#423751 · 11.07:1
AAA on whitealready passes
#423751
The quick fox
#806C9B · 4.54:1
AA on black+25% L
#806C9B
The quick fox
#A091B4 · 7.20:1
AAA on black+37% L
#A091B4

Large text — 24px regular or 18.66px bold and above — only needs 3:1, so #423751 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
#423751 on white: 11.07:1
AA ✓ pass · AA-large · AAA
Aa
#423751 on black: 1.90:1
AA ✗ fail · AA-large · AAA
Against the neutral ladder

Contrast is symmetric, so each row covers both directions: #423751 as text on that neutral, and that neutral as text on #423751.

NeutralRatioBoth directions
White11.07:1AaAa
Slate 5010.58:1AaAa
Slate 10010.11:1AaAa
Slate 2008.98:1AaAa
Slate 3007.46:1AaAa
Slate 4004.32:1AaAa
Slate 5002.33:1AaAa
Slate 6001.46:1AaAa
Slate 7001.07:1AaAa
Slate 8001.32:1AaAa
Slate 9001.61:1AaAa
Black1.90:1AaAa
Colour vision deficiency
true color
protanopia · #323B52
deuteranopia · #343C50
tritanopia · #403B40

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. #423751 is pinned to step 900; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F7F6F8
#EFEDF2
#DDD8E3
#C5BCD2
#A89BBB
#8C79A4
#776392
#635379
#4F4261
#423751
#25202D
Base = 900Lightest = 50 · #F7F6F8Darkest = 950 · #25202DText step on white = 600
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 0.012 303.5);
  --brand-100: oklch(0.94 0.018 303.5);
  --brand-200: oklch(0.88 0.028 303.5);
  --brand-300: oklch(0.80 0.036 303.5);
  --brand-400: oklch(0.72 0.043 303.5);
  --brand-500: oklch(0.64 0.046 303.5);
  --brand-600: oklch(0.56 0.046 303.5);
  --brand-700: oklch(0.48 0.043 303.5);
  --brand-800: oklch(0.40 0.039 303.5);
  --brand-900: oklch(0.32 0.032 303.5);
  --brand-950: oklch(0.24 0.025 303.5);
}

Colors that work with #423751

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#F7F6F9
Tinted page background
Border#D5CEDE
Hairlines and dividers
Muted text#6F5D89
Captions on the surface
Accent#4E5434
Second voice, not a rival
Dark variant#3E344C
Hover, pressed, headers
Light variant#F2F0F5
Selected rows, tints
Dark surface#1B1721
Dark-mode background
Hover#31293C
One step down in lightness
Pressed#1F1A27
Two steps down
Disabled#796494
Chroma pulled out
Focus ring#4B3865
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 #423751

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

Works well for
  • Body text and links on white
  • Charts, tags and secondary surfaces
  • Headers, footers and dark-mode surfaces
  • Brand accents, badges and data highlights
Use with care
  • Text on black or near-black surfaces
  • 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.

The muted chroma softens the association — it reads considered rather than loud, which suits long-form and data-heavy screens. 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
  • Weight73/100
  • TemperatureCool
  • ApproachabilityBalanced

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#465137
Analogous left#373951
Analogous right#4F3751
Split-complement 1#514F37
Split-complement 2#395137
Triadic 1#514237
Triadic 2#375142
Tetradic#513739
On the wheel
Base+30°−30°+120°+240°+180°265°

#423751 sits at 265°. Every dot is a harmony position and links to its own page in the table alongside.

RGB percentages

Red25.9%
Green21.6%
Blue31.8%
R · 0–255
66
0x42
G · 0–255
55
0x37
B · 0–255
81
0x51

CMYK percentages

Cyan18.5%
Magenta32.1%
Yellow0.0%
Key (black)68.2%

Total ink coverage is 119%. Most commercial presses cap around 300% — above that, sheets stop drying properly.

Color previews

#423751 text on a black background

contrast 1.90:1

Card sample

#423751 text on a white background

contrast 11.07:1

Card sample

#423751 on grey

10.11:1

#423751 on its own surface

10.28:1

#423751 on its dark surface

1.59:1

CSS3 live lab

Text font color

The quick brown fox

color: #423751;
Background color
Panel with #423751 background
background-color: #423751;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #423751;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(66, 55, 81, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(66, 55, 81, 0.45);
Border & gradient
Gradient panel
border: 3px solid #423751;
background: linear-gradient(135deg, #423751, #51374F);
Gradient text

Gradient headline

background: linear-gradient(90deg, #423751, #513748);
-webkit-background-clip: text;
color: transparent;
Focus ring
Focused control
outline: 2px solid #423751;
outline-offset: 3px;
Underline & caret

Marked up text

text-decoration-color: #423751;
caret-color: #423751;
Left rule
Pull quote or callout
border-left: 4px solid #423751;
Ring + tint
Selected chip
background: #F2F0F5;
box-shadow: inset 0 0 0 2px #423751;
Conic badge
68%
background: conic-gradient(#423751 68%, #e2e8f0 0);

Transparency

What each alpha value actually composites to. The top row is #423751 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(66, 55, 81, 0.5)
rgb(66 55 81 / 50%)
#42375180
hsl(265 19% 27% / 50%)
color-mix(in srgb, #423751 50%, transparent)
Alpha8-digit hexFlat on white
10%#4237511a#ECEBEE
20%#42375133#D9D7DC
40%#42375166#B3AFB9
60%#42375199#8E8797
80%#423751cc#685F74

Gradients from #423751

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, #605076, #423751 45%, #3E344C);
Duotone
A short hue run reads richer than a flat fill
background: linear-gradient(120deg, #423751, #3F2B3B);
Complement sweep
Loud — keep it behind large type only
background: linear-gradient(90deg, #423751, #465137);
Spotlight
Hero panels and app headers
background: radial-gradient(120% 120% at 20% 0%, #6F5C88 0%, #423751 45%, #3E344C 100%);
Soft wash
Section backgrounds that stay readable
background: linear-gradient(180deg, #F7F6F9, #ffffff);
Mesh
Ambient background, no image weight
background: radial-gradient(60% 60% at 15% 20%, #4C516F 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #634363 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #3E344C 0%, transparent 65%), #423751;

Monochromatic scale

Palettes built from #423751

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.

#423751 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 1.90:1 — lift it to #806C9B 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.

#423751, answered

What color is #423751?

#423751 is a dark soft violet, closest to Dark Slate Blue (ΔE2000 14.1). It sits at 265° on the hue wheel with 19% saturation and 27% lightness, which reads as cool.

What is the RGB value of #423751?

rgb(66, 55, 81) — 66 red, 55 green and 81 blue out of 255, or 25.9% / 21.6% / 31.8% by channel.

What is #423751 in HSL and HSV?

hsl(265, 19%, 27%) and hsv(265, 32%, 32%). HSL is what CSS takes; HSV is what your design tool's picker shows, which is why the saturation numbers rarely match.

Is #423751 a light or a dark color?

It is a dark color. Relative luminance is 0.0448 and perceived brightness is 24%, so white text on it reaches 11.07:1.

Should I use black or white text on #423751?

White. It scores 11.07:1 against #423751, versus 1.90:1 for black — AAA at any size.

Is #423751 accessible on a white background?

#423751 on white scores 11.07:1, which clears AAA at every size.

What is the complementary color of #423751?

#465137 sits directly opposite on the wheel. Softer options are the split-complements #514F37 and #395137, which give the same contrast with far less vibration.

What colors go well with #423751?

For interface work: #F7F6F9 as the surface, #D5CEDE for borders, #6F5D89 for secondary text, #4E5434 as an accent and #3E344C for hover and pressed states. For a palette, the analogous pair #373951 and #4F3751 stays calm, while #465137 is the loudest partner.

What is #423751 in CMYK for printing?

cmyk(19%, 32%, 0%, 68%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #423751 warm or cool?

Cool — it scores 60 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #4C3751; nudged cooler, #373652.

Which Tailwind color is closest to #423751?

The zinc family — its 500 step is #71717a, ΔE2000 21.6 away. That is a visible difference, so define #423751 as a custom token rather than reaching for the built-in.

How do I use #423751 in Tailwind CSS?

Inline it as an arbitrary value with bg-[#423751] or text-[#423751], 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 #423751 with 50% opacity?

rgba(66, 55, 81, 0.5), or #42375180 in eight-digit hex. Over white that composites to #A19BA8; over black, #211C29.

Is #423751 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 #423751 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 moderate chroma the association is present but not shouted.

What gradient works with #423751?

The safest is same-hue elevation: linear-gradient(135deg, #605076, #423751 45%, #3E344C). For more colour, a short hue run to #3F2B3B keeps it rich without turning muddy.

Work with #423751 in the Color Lab

Every tool opens with this colour already loaded.

Every value on this page is computed from #423751 at request time — conversions, contrast ratios and ΔE distances are calculated, never looked up.