What color is #042C39?

#042C39 is a very dark, vivid cyan. In RGB it is rgb(4, 44, 57), and in HSL hsl(195, 87%, 12%).

Is #042C39 accessible as text?

On white, #042C39 has a contrast ratio of 14.74:1 (passes WCAG AA for body text); on black it is 1.42:1 (fails). For text placed on #042C39, use white for the best readability.

What is the closest Tailwind color to #042C39?

The nearest Tailwind CSS token is teal-950 (#022F2E).

What colors go well with #042C39?

#042C39 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #391104. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #042C39 below.

Is #042C39 good for buttons?

#042C39 works well for buttons and highlights, but use white text on #042C39 — black text only reaches 1.42:1, below the 4.5:1 needed for normal-size labels.

Is #042C39 the same as CSS midnightblue?

No — #042C39 is not the CSS named color midnightblue, but midnightblue (#191970) is the closest CSS named color.

#042C39 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #042C39

Not just a swatch — here's how #042C39 works with other colors. Named schemes with #042C39 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #042C39 Accent #A6C4BF Surface #DEDABF Secondary #9AA0A0 Anchor #1E344A

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

Nordic Calm Accent · 5 colors

Accent #042C39 Secondary #AEB4B8 Surface #F1F2F0 Support #7B93A5 Anchor #2E3236

Prussian Blue keeps this Nordic scheme quiet — cool greys and a soft white around it, a muted-blue support and a charcoal anchor.

Tech Product Signal · 5 colors

Signal #042C39 Surface #14161A Highlight #F4F6F8 Secondary #596672 Accent #2B4B58

Prussian Blue is the vivid signal in this product UI — on a near-black surface with cool white, a slate grey and a lighter tint of Prussian Blue.

Vintage Leather Lead · 5 colors

Lead #042C39 Secondary #6F5116 Surface #E2DCC0 Accent #385244 Anchor #56233E

Prussian 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 #F6F4EF Accent #042C39 Secondary #424D52 Support #969386 Ink #16140F

Prussian 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 Prussian Blue carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #042C39 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 36/100

Cool

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

Softness 28/100

Low

Firm and assertive — carries weight and contrast.

Depth 69/100

High

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

Naturalness 1/100

Very low

Reads engineered rather than organic — synthetic, digital.

Vintage feel 27/100

Low

A faint retro warmth without tipping into sepia.

Luxury 71/100

High

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

Brand distinctiveness 19/100

Very low

Quiet and neutral — a supporting tone, not a signature.

UI accent fit 23/100

Low

Weak as an action color — too pale, too dark or too muted to signal.

Surface fit 53/100

Moderate

Usable as a tinted surface in measured doses.

Print safety 87/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #042C39

For UI

For branding

For interior

For fashion

People also use #042C39 with

Hunter Green Navy Oxblood Platinum Dark Slate 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 14.7:1. Use

Subtle surface Use #B6E0EE for cards and hover fills. Tint 80

Avoid beside #041A39 — 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 #042C39 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: #042C39;
  --color-base-rgb: 4 44 57;
  --color-base-oklch: oklch(27.4% 0.048 224.9);
  --color-50: #F0FBFE;
  --color-100: #D8F4FD;
  --color-200: #B3E8FA;
  --color-300: #7FD4F0;
  --color-400: #51BDE1;
  --color-500: #2EA1C7;
  --color-600: #2B7C97;
  --color-700: #24596B;
  --color-800: #1C3B45;
  --color-900: #13242A;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  prussian-blue: {
    50: '#F0FBFE',
    100: '#D8F4FD',
    200: '#B3E8FA',
    300: '#7FD4F0',
    400: '#51BDE1',
    500: '#2EA1C7',
    600: '#2B7C97',
    700: '#24596B',
    800: '#1C3B45',
    900: '#13242A',
  },
}

$base: #042C39;
$base-ink: #FFFFFF;
$base-50: #F0FBFE;
$base-100: #D8F4FD;
$base-200: #B3E8FA;
$base-300: #7FD4F0;
$base-400: #51BDE1;
$base-500: #2EA1C7;
$base-600: #2B7C97;
$base-700: #24596B;
$base-800: #1C3B45;
$base-900: #13242A;
$base-hover: #03232E;
$base-subtle: #8FD2E8;

{
    "color": {
        "base": {
            "value": "#042C39",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F0FBFE",
                "type": "color"
            },
            "100": {
                "value": "#D8F4FD",
                "type": "color"
            },
            "200": {
                "value": "#B3E8FA",
                "type": "color"
            },
            "300": {
                "value": "#7FD4F0",
                "type": "color"
            },
            "400": {
                "value": "#51BDE1",
                "type": "color"
            },
            "500": {
                "value": "#2EA1C7",
                "type": "color"
            },
            "600": {
                "value": "#2B7C97",
                "type": "color"
            },
            "700": {
                "value": "#24596B",
                "type": "color"
            },
            "800": {
                "value": "#1C3B45",
                "type": "color"
            },
            "900": {
                "value": "#13242A",
                "type": "color"
            }
        }
    }
}