What color is #28366B?

#28366B is a dark blue. In RGB it is rgb(40, 54, 107), and in HSL hsl(227, 46%, 29%).

Is #28366B accessible as text?

On white, #28366B has a contrast ratio of 11.47:1 (passes WCAG AA for body text); on black it is 1.83:1 (fails). For text placed on #28366B, use white for the best readability.

What is the closest Tailwind color to #28366B?

The nearest Tailwind CSS token is indigo-900 (#312C85).

What colors go well with #28366B?

#28366B pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #6C5D28. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #28366B below.

Is #28366B good for buttons?

#28366B works well for buttons and highlights, but use white text on #28366B — black text only reaches 1.83:1, below the 4.5:1 needed for normal-size labels.

Is #28366B the same as CSS darkslateblue?

No — #28366B is not the CSS named color darkslateblue, but darkslateblue (#483D8B) is the closest CSS named color.

#28366B Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #28366B

Not just a swatch — here's how #28366B works with other colors. Named schemes with #28366B in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #28366B Accent #A5C4C2 Surface #EAD5C0 Secondary #9AA0A1 Anchor #21344A

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

Luxury Packaging Feature · 5 colors

Feature #28366B Anchor #141210 Accent #DC9659 Secondary #252933 Surface #F3ECE3

Yale 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 #28366B Anchor #2A2A2E Secondary #6E6E74 Surface #EEE5DB Accent #1C163A

Yale 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 Yale Blue.

Vintage Leather Lead · 5 colors

Lead #28366B Secondary #7F4535 Surface #EED7C2 Accent #365246 Anchor #582239

Yale 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 #28366B Secondary #596074 Support #9D8F88 Ink #18140F

Yale 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 Yale Blue carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #28366B 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 29/100

Cool

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

Softness 32/100

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 44/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 69/100

High

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

Brand distinctiveness 36/100

Low

Recognisable but shares space with nearby hues.

UI accent fit 52/100

Moderate

Workable accent with care around contrast.

Surface fit 34/100

Low

Usable as a tinted surface in measured doses.

Print safety 84/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #28366B

For UI

For branding

For interior

For fashion

People also use #28366B with

Teal Blue Indigo Dark Olive Green Gainsboro Gunmetal Gray

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 11.5:1. Use

Subtle surface Use #CFD4E7 for cards and hover fills. Tint 80

Avoid beside #30286C — 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 #28366B 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: #28366B;
  --color-base-rgb: 40 54 107;
  --color-base-oklch: oklch(35.1% 0.094 269.9);
  --color-50: #F3F5FB;
  --color-100: #E1E5F5;
  --color-200: #C4CCE9;
  --color-300: #9AA7D5;
  --color-400: #7383BF;
  --color-500: #5263A3;
  --color-600: #44517E;
  --color-700: #353D5A;
  --color-800: #252A3C;
  --color-900: #181B25;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  yale-blue: {
    50: '#F3F5FB',
    100: '#E1E5F5',
    200: '#C4CCE9',
    300: '#9AA7D5',
    400: '#7383BF',
    500: '#5263A3',
    600: '#44517E',
    700: '#353D5A',
    800: '#252A3C',
    900: '#181B25',
  },
}

$base: #28366B;
$base-ink: #FFFFFF;
$base-50: #F3F5FB;
$base-100: #E1E5F5;
$base-200: #C4CCE9;
$base-300: #9AA7D5;
$base-400: #7383BF;
$base-500: #5263A3;
$base-600: #44517E;
$base-700: #353D5A;
$base-800: #252A3C;
$base-900: #181B25;
$base-hover: #202C56;
$base-subtle: #B6BEDC;

{
    "color": {
        "base": {
            "value": "#28366B",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F5FB",
                "type": "color"
            },
            "100": {
                "value": "#E1E5F5",
                "type": "color"
            },
            "200": {
                "value": "#C4CCE9",
                "type": "color"
            },
            "300": {
                "value": "#9AA7D5",
                "type": "color"
            },
            "400": {
                "value": "#7383BF",
                "type": "color"
            },
            "500": {
                "value": "#5263A3",
                "type": "color"
            },
            "600": {
                "value": "#44517E",
                "type": "color"
            },
            "700": {
                "value": "#353D5A",
                "type": "color"
            },
            "800": {
                "value": "#252A3C",
                "type": "color"
            },
            "900": {
                "value": "#181B25",
                "type": "color"
            }
        }
    }
}