What color is #123740?

#123740 is a very dark cyan. In RGB it is rgb(18, 55, 64), and in HSL hsl(192, 56%, 16%).

Is #123740 accessible as text?

On white, #123740 has a contrast ratio of 12.76:1 (passes WCAG AA for body text); on black it is 1.65:1 (fails). For text placed on #123740, use white for the best readability.

What is the closest Tailwind color to #123740?

The nearest Tailwind CSS token is cyan-950 (#053345).

What colors go well with #123740?

#123740 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #401B12. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #123740 below.

Is #123740 good for buttons?

#123740 works well for buttons and highlights, but use white text on #123740 — black text only reaches 1.65:1, below the 4.5:1 needed for normal-size labels.

Is #123740 the same as CSS darkslategray?

No — #123740 is not the CSS named color darkslategray, but darkslategray (#2F4F4F) is the closest CSS named color.

#123740 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #123740

Not just a swatch — here's how #123740 works with other colors. Named schemes with #123740 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #123740 Accent #A6C4BF Surface #DFDABF Secondary #9AA0A0 Anchor #1E3549

Gunmetal Gray 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 #123740 Secondary #AEB4B8 Surface #F1F2F0 Support #7B94A5 Anchor #2E3236

Gunmetal Gray 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 #123740 Surface #14161A Highlight #F4F6F8 Secondary #596672 Accent #37575F

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

Vintage Leather Lead · 5 colors

Lead #123740 Secondary #705116 Surface #E3DCC0 Accent #395244 Anchor #56233E

Gunmetal Gray 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 #123740 Secondary #4D595C Support #969386 Ink #16140F

Gunmetal Gray 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 Gunmetal Gray carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #123740 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 37/100

Cool

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

Softness 32/100

Low

Middle-weight — neither delicate nor heavy.

Depth 65/100

High

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

Naturalness 2/100

Very low

Reads engineered rather than organic — synthetic, digital.

Vintage feel 30/100

Low

A faint retro warmth without tipping into sepia.

Luxury 68/100

High

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

Brand distinctiveness 17/100

Very low

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

UI accent fit 31/100

Low

Workable accent with care around contrast.

Surface fit 51/100

Moderate

Usable as a tinted surface in measured doses.

Print safety 88/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #123740

For UI

For branding

For interior

For fashion

People also use #123740 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 12.8:1. Use

Subtle surface Use #C3DFE5 for cards and hover fills. Tint 80

Avoid beside #122740 — 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 #123740 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: #123740;
  --color-base-rgb: 18 55 64;
  --color-base-oklch: oklch(31.5% 0.044 216.6);
  --color-50: #F3FAFC;
  --color-100: #DFF2F7;
  --color-200: #BFE4ED;
  --color-300: #93CDDC;
  --color-400: #6BB5C7;
  --color-500: #4998AC;
  --color-600: #3E7684;
  --color-700: #31555E;
  --color-800: #23393E;
  --color-900: #172326;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  gunmetal-gray: {
    50: '#F3FAFC',
    100: '#DFF2F7',
    200: '#BFE4ED',
    300: '#93CDDC',
    400: '#6BB5C7',
    500: '#4998AC',
    600: '#3E7684',
    700: '#31555E',
    800: '#23393E',
    900: '#172326',
  },
}

$base: #123740;
$base-ink: #FFFFFF;
$base-50: #F3FAFC;
$base-100: #DFF2F7;
$base-200: #BFE4ED;
$base-300: #93CDDC;
$base-400: #6BB5C7;
$base-500: #4998AC;
$base-600: #3E7684;
$base-700: #31555E;
$base-800: #23393E;
$base-900: #172326;
$base-hover: #0E2C33;
$base-subtle: #A3CFDA;

{
    "color": {
        "base": {
            "value": "#123740",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3FAFC",
                "type": "color"
            },
            "100": {
                "value": "#DFF2F7",
                "type": "color"
            },
            "200": {
                "value": "#BFE4ED",
                "type": "color"
            },
            "300": {
                "value": "#93CDDC",
                "type": "color"
            },
            "400": {
                "value": "#6BB5C7",
                "type": "color"
            },
            "500": {
                "value": "#4998AC",
                "type": "color"
            },
            "600": {
                "value": "#3E7684",
                "type": "color"
            },
            "700": {
                "value": "#31555E",
                "type": "color"
            },
            "800": {
                "value": "#23393E",
                "type": "color"
            },
            "900": {
                "value": "#172326",
                "type": "color"
            }
        }
    }
}