Color reference

#3A42CE color reference

Vivid Mid-light Blue

This is a vivid, mid-light blue under the deterministic OKLCH hue, lightness, and chroma ranges. Its closest standardized CSS named color is Slate Blue (#6A5ACD), measured with straight-line OKLab distance.

Descriptive label
Vivid Mid-light Blue
Recommended text
White · 7.37:1
Relative luminance
0.092522
Build a palette from #3A42CE in Palette Generator Convert #3A42CE in Color Converter
Formats UI preview Contrast 50–900 scale Harmonies Matches Related colors Color vision Exports

Copyable values

#3A42CE in common color formats

Values are calculated from the same opaque sRGB color. Display rounding does not alter the internal calculations.

Color conversions for #3A42CE
Format Value Action
HEX #3A42CE
RGB rgb(58 66 206)
HSL hsl(237 60.16% 51.76%)
HSV hsv(237 71.84% 80.78%)
HWB hwb(237 22.75% 19.22%)
XYZ D65 color(xyz-d65 0.148324 0.092517 0.593986)
LAB lab(35.1797% 34.2836 -74.7544)
LCH lch(35.1797% 82.241 294.637)
OKLAB oklab(46.9988% 0.008976 -0.210957)
OKLCH oklch(46.9988% 0.211147 272.4364)

Real-world test

Try #3A42CE on interface components

Preview the source as a primary action, subtle status, form treatment, and card surface. Persistent state controls help touch and keyboard users inspect the same normal, hover, and active colors.

Normal state uses #3A42CE with white text at 7.37:1.

Action

Primary button

Use the controls above or point to and press the button to inspect its visual states.

Status

Subtle alert badge

A 12% source tint over white provides the background; readable text is selected separately.

Ready for review

Form

Border and focus ring

Source ring on white: 7.37:1 · meets the 3:1 non-text threshold where applicable.

Surface

Card component

The selected state becomes the card surface with its strongest black-or-white text pairing.

Design system Color decision ready Review states and surrounding surfaces before shipping.

Accessibility diagnostics

WCAG contrast for exact color pairs

Each result applies only to the named foreground, background, text size, and requirement. It is not a complete accessibility or component-conformance claim.

Source #3A42CE Exact pair assessment Results for source text on white appear below.

On white

7.37:1

  • Pass AA normal text · 4.5:1
  • Pass AAA normal text · 7:1
  • Pass AA large text · 3:1
  • Pass UI/non-text where applicable · 3:1
Source #3A42CE Exact pair assessment Results for source text on black appear below.

On black

2.85:1

  • Fail AA normal text · 4.5:1
  • Fail AAA normal text · 7:1
  • Fail AA large text · 3:1
  • Fail UI/non-text where applicable · 3:1

Use guidance

What this color may be suitable for

Pass in a tested context

Normal-sized text

#3A42CE reaches 7.05:1 on Hue Codex paper, meeting WCAG AA for normal text in that exact pairing.

Potential fit

Controls and interface graphics

Against Hue Codex paper, the color reaches 7.05:1. That meets the 3:1 color-contrast threshold where WCAG 1.4.11 applies, but states, shape, and non-color cues still need review.

Readable pairing available

Colored surface or button fill

White text provides the stronger black/white pairing on #3A42CE at 7.37:1. This validates only that text pair, not hover, focus, disabled, or adjacent-color states.

Distinctive accent

Palette role

Its OKLCH chroma of 0.2111 gives it enough visual presence for an accent or primary role when the tested foreground and neighboring colors pass.

Pair available

Color used as foreground

The stronger black/white background is white at 7.37:1. Always retest against the actual rendered background and text size.

Tested backgrounds

Foreground pairing comparison

#3A42CE foreground contrast on tested backgrounds
Pair Background Contrast ratio
White#FFFFFF 7.37:1
Hue Codex paper#FBFAF5 7.05:1
Soft neutral#F2EFE6 6.41:1
Black#000000 2.85:1
Hue Codex ink#10212B 2.24:1
Check #3A42CE on another background in Contrast Checker

Design-system starting point

A perceptual 50–900 reference scale

The source color is preserved at the nearest lightness step. Other swatches keep its OKLCH hue, moderate chroma toward the extremes, and reduce chroma only when needed to remain in sRGB.

50
100
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400
500
600 #3A42CE Source
700
800
900

This is a Hue Codex reference scale, not a claim that the values match Tailwind, Material, or another framework’s named palette.

Adjust the #3A42CE scale in Tints, Shades & Tones

Color relationships

Complementary, analogous, and triadic colors

Hue rotations use OKLCH while preserving lightness and requested chroma. When a rotated result falls outside sRGB, chroma is reduced deterministically and disclosed.

Complementary

Source #3A42CE
Complement Chroma fitted to sRGB

Analogous

Source #3A42CE
Analogous −30° Chroma fitted to sRGB
Analogous +30°

Triadic

Source #3A42CE
Triad +120° Chroma fitted to sRGB
Triad +240° Chroma fitted to sRGB

Applied pairing

A small interface check

The source anchors the main action while the complement marks a secondary status. Contrast is selected separately for each fill.

Project color Vivid Mid-light Blue
Complement
Explore #3A42CE in Color Harmonies

Distance matching

Closest standardized and framework colors

Matches use straight-line OKLab distance ×100. A smaller value means the coordinates are closer in this model; it is not a claim that two tokens are interchangeable in a design system.

CSS named color

Slate Blue

#6A5ACD

OKLab distance ×100: 9.43

Tailwind v4 default

indigo-700

oklch(45.7% 0.24 277.023)

OKLab distance ×100: 3.64 · sRGB preview #432DD7

Print boundary

Pantone match not estimated

Reliable print matching needs licensed reference data plus a defined ink, paper, profile, and viewing condition.

Read the print methodology

Color-vision screening

Approximate color-vision-deficiency views

These encoded-sRGB matrix previews are screening approximations. They help reveal possible color-only distinctions but do not reproduce every person’s vision or establish accessibility conformance.

Original#3A42CE
Approx.

Protanopia

Red-vision deficiency approximation

Original#3A42CE
Approx.

Deuteranopia

Green-vision deficiency approximation

Original#3A42CE
Approx.

Tritanopia

Blue-yellow deficiency approximation

Original#3A42CE
Approx.

Achromatopsia

Monochromatic-vision approximation

Test #3A42CE with a complete palette in the CVD Simulator

Ready to use

Copy framework-ready color tokens

Exports preserve the source, readable foreground, and generated 50–900 scale. Tailwind v4 CSS-first and Tailwind v3 JavaScript-config formats are labeled separately.

CSS custom properties

Semantic aliases and the complete 50–900 scale.

:root {
  --color-primary: #3A42CE;
  --color-on-primary: #FFFFFF;
  --color-primary-oklch: oklch(46.9988% 0.211147 272.4364);
  --color-primary-50: #F2F5FF;
  --color-primary-100: #D3DDFF;
  --color-primary-200: #B0C1FF;
  --color-primary-300: #8EA4FF;
  --color-primary-400: #6F86FE;
  --color-primary-500: #576AEA;
  --color-primary-600: #3A42CE;
  --color-primary-700: #3033B9;
  --color-primary-800: #211997;
  --color-primary-900: #150072;
}

Tailwind v4 CSS-first theme

Current @theme syntax for bg-brand, text-brand, and scale utilities.

@import "tailwindcss";

@theme {
  --color-brand: #3A42CE;
  --color-brand-foreground: #FFFFFF;
  --color-brand-50: #F2F5FF;
  --color-brand-100: #D3DDFF;
  --color-brand-200: #B0C1FF;
  --color-brand-300: #8EA4FF;
  --color-brand-400: #6F86FE;
  --color-brand-500: #576AEA;
  --color-brand-600: #3A42CE;
  --color-brand-700: #3033B9;
  --color-brand-800: #211997;
  --color-brand-900: #150072;
}

Tailwind v3 / legacy config

CommonJS theme.extend.colors for JavaScript-config projects.

module.exports = {
  theme: {
    extend: {
      colors: {
        brand: {
          '50': '#F2F5FF',
          '100': '#D3DDFF',
          '200': '#B0C1FF',
          '300': '#8EA4FF',
          '400': '#6F86FE',
          '500': '#576AEA',
          '600': '#3A42CE',
          '700': '#3033B9',
          '800': '#211997',
          '900': '#150072',
          DEFAULT: '#3A42CE',
          foreground: '#FFFFFF',
        },
      },
    },
  },
};

Sass variables

Semantic source, foreground, OKLCH, and scale variables.

$color-primary: #3A42CE;
$color-on-primary: #FFFFFF;
$color-primary-oklch: oklch(46.9988% 0.211147 272.4364);
$color-primary-50: #F2F5FF;
$color-primary-100: #D3DDFF;
$color-primary-200: #B0C1FF;
$color-primary-300: #8EA4FF;
$color-primary-400: #6F86FE;
$color-primary-500: #576AEA;
$color-primary-600: #3A42CE;
$color-primary-700: #3033B9;
$color-primary-800: #211997;
$color-primary-900: #150072;

Modern color-mix()

Static fallbacks followed by OKLab tint and shade declarations.

:root {
  --color-primary: #3A42CE;
  --color-primary-tint: #B0C1FF;
  --color-primary-tint: color-mix(in oklab, var(--color-primary) 72%, white);
  --color-primary-shade: #3033B9;
  --color-primary-shade: color-mix(in oklab, var(--color-primary) 82%, black);
}

JSON design data

Source formats, readable text, and the generated scale.

{
    "name": "Vivid Mid-light Blue",
    "hex": "#3A42CE",
    "rgb": "rgb(58 66 206)",
    "oklch": "oklch(46.9988% 0.211147 272.4364)",
    "recommendedText": "#FFFFFF",
    "scale": {
        "50": "#F2F5FF",
        "100": "#D3DDFF",
        "200": "#B0C1FF",
        "300": "#8EA4FF",
        "400": "#6F86FE",
        "500": "#576AEA",
        "600": "#3A42CE",
        "700": "#3033B9",
        "800": "#211997",
        "900": "#150072"
    }
}

Continue the decision

Use #3A42CE in a complete workflow

Reference values are a starting point. Test the color in its real role, background, states, typography, and surrounding palette before shipping.

Adjust #3A42CE in Color PickerStart with this exact color and white as the working background for role and accessibility decisions. Build a palette from #3A42CE in Palette GeneratorUse this exact HEX as the seed for a deterministic, role-based palette. Check #3A42CE on white in Contrast CheckerStart with this color as the foreground and white as the background, then test the real pair.