What color is #2A378B?

#2A378B is a dark blue. In RGB it is rgb(42, 55, 139), and in HSL hsl(232, 54%, 35%).

Is #2A378B accessible as text?

On white, #2A378B has a contrast ratio of 10.41:1 (passes WCAG AA for body text); on black it is 2.02:1 (fails). For text placed on #2A378B, use white for the best readability.

What is the closest Tailwind color to #2A378B?

The nearest Tailwind CSS token is blue-900 (#1C398E).

What colors go well with #2A378B?

#2A378B pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #897D29. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #2A378B below.

Is #2A378B good for buttons?

#2A378B works well for buttons and highlights, but use white text on #2A378B — black text only reaches 2.02:1, below the 4.5:1 needed for normal-size labels.

Is #2A378B the same as CSS darkslateblue?

No — #2A378B is not the CSS named color darkslateblue, but darkslateblue (#483D8B) is the closest CSS named color.

#2A378B Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #2A378B

Not just a swatch — here's how #2A378B works with other colors. Named schemes with #2A378B in its natural role, and a note on why the supporting colors balance it.

Luxury Packaging Feature · 5 colors

Feature #2A378B Anchor #141210 Accent #DC9659 Secondary #252833 Surface #F3ECE3

Dark Slate Blue carries the depth in this luxury scheme, offset by a brass accent and near-black and held together by a deep neutral and an off-white surface.

Moody Editorial Color · 5 colors

Color #2A378B Anchor #2A2A2E Secondary #6E6E74 Surface #EEE5DB Accent #25174F

Dark Slate Blue adds the colour to this moody editorial scheme — charcoal and a mid-grey around it, a bone highlight, and a muted jewel accent drawn from Dark Slate Blue.

Coastal Morning Lead · 5 colors

Lead #2A378B Accent #A5C4C2 Surface #EAD5C0 Secondary #9AA0A1 Anchor #21344A

Dark Slate Blue opens this coastal palette with sea-glass and warm sand alongside it, grounded by driftwood grey and a deep-navy anchor.

Vintage Leather Lead · 5 colors

Lead #2A378B Secondary #7F4535 Surface #EED7C2 Accent #365247 Anchor #582239

Dark Slate Blue plays the worn-leather lead, deepened by saddle brown and an oxblood anchor, softened by aged cream and cooled by a muted forest green.

Minimal Editorial Surface · 5 colors

Surface #F8F4EF Accent #2A378B Secondary #5E6886 Support #9D8F88 Ink #18140F

Dark Slate Blue is the single accent in this high-contrast editorial system — set on near-white paper against near-black ink, with a warm grey and a desaturated tint of Dark Slate Blue carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #2A378B actually behaves in design work — read from its OKLCH lightness, chroma and hue, not just its raw numbers. Ten signals to help you decide where this color earns its place.

Warmth 19/100

Cool

Reads cool and recessive — calming, technical, good for trust-led UI.

Softness 30/100

Low

Firm and assertive — carries weight and contrast.

Depth 64/100

High

Deep and grounding — anchors a layout, strong dark-mode base.

Naturalness 0/100

Very low

Reads engineered rather than organic — synthetic, digital.

Vintage feel 35/100

Low

A faint retro warmth without tipping into sepia.

Luxury 66/100

High

Restrained and premium — deep, quiet, high-end packaging and fashion.

Brand distinctiveness 54/100

Moderate

Recognisable but shares space with nearby hues.

UI accent fit 68/100

High

Strong interactive accent — visible and can carry a legible label.

Surface fit 18/100

Very low

Too saturated or mid-toned for big areas — keep it to accents.

Print safety 77/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #2A378B

For UI

For branding

For interior

For fashion

People also use #2A378B with

Steel Blue Dark Slate Blue Olive Gainsboro Prussian Blue

UI roles & guardrails

Primary action Safe as a filled button with white label. AAA

Body text Passes on white at 16px and above. Pass

Large display Fine for headings 24px+ on white. Pass

Background Pair with white text at 10.4:1. Use

Subtle surface Use #D1D4EB for cards and hover fills. Tint 80

Avoid beside #3C2989 — the hue gap is too small to read as intentional. Clash

In real applications

Not a swatch to memorise — a color to build with. Here is #2A378B at work across the surfaces designers actually ship.

Website / UI

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Dashboard

Revenue

$48.2k ▲ 12%

Brand

AVELINE

Studio

Poster

Nov 14 · 8PM

NIGHT
MARKET

Packaging

BLOOM

Botanical Wash

250 ml

Interior

Every model

Export

:root {
  --color-base: #2A378B;
  --color-base-rgb: 42 55 139;
  --color-base-oklch: oklch(38.0% 0.140 271.4);
  --color-50: #F3F4FC;
  --color-100: #DFE2F6;
  --color-200: #C0C6EC;
  --color-300: #959EDA;
  --color-400: #6C78C6;
  --color-500: #4B58AA;
  --color-600: #3F4883;
  --color-700: #32375D;
  --color-800: #23273D;
  --color-900: #171926;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  dark-slate-blue: {
    50: '#F3F4FC',
    100: '#DFE2F6',
    200: '#C0C6EC',
    300: '#959EDA',
    400: '#6C78C6',
    500: '#4B58AA',
    600: '#3F4883',
    700: '#32375D',
    800: '#23273D',
    900: '#171926',
  },
}

$base: #2A378B;
$base-ink: #FFFFFF;
$base-50: #F3F4FC;
$base-100: #DFE2F6;
$base-200: #C0C6EC;
$base-300: #959EDA;
$base-400: #6C78C6;
$base-500: #4B58AA;
$base-600: #3F4883;
$base-700: #32375D;
$base-800: #23273D;
$base-900: #171926;
$base-hover: #212B6E;
$base-subtle: #B9BEE2;

{
    "color": {
        "base": {
            "value": "#2A378B",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F4FC",
                "type": "color"
            },
            "100": {
                "value": "#DFE2F6",
                "type": "color"
            },
            "200": {
                "value": "#C0C6EC",
                "type": "color"
            },
            "300": {
                "value": "#959EDA",
                "type": "color"
            },
            "400": {
                "value": "#6C78C6",
                "type": "color"
            },
            "500": {
                "value": "#4B58AA",
                "type": "color"
            },
            "600": {
                "value": "#3F4883",
                "type": "color"
            },
            "700": {
                "value": "#32375D",
                "type": "color"
            },
            "800": {
                "value": "#23273D",
                "type": "color"
            },
            "900": {
                "value": "#171926",
                "type": "color"
            }
        }
    }
}

Palettes built on #2A378B

Color Lab

Pairs with #2A378B

UI roles & guardrails

In real applications

Scales

Every model

Export