What color is #173040?

#173040 is a very dark cyan-blue. In RGB it is rgb(23, 48, 64), and in HSL hsl(203, 47%, 17%).

Is #173040 accessible as text?

On white, #173040 has a contrast ratio of 13.70:1 (passes WCAG AA for body text); on black it is 1.53:1 (fails). For text placed on #173040, use white for the best readability.

What is the closest Tailwind color to #173040?

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

What colors go well with #173040?

#173040 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #402717. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #173040 below.

Is #173040 good for buttons?

#173040 works well for buttons and highlights, but use white text on #173040 — black text only reaches 1.53:1, below the 4.5:1 needed for normal-size labels.

Is #173040 the same as CSS darkslategray?

No — #173040 is not the CSS named color darkslategray, but darkslategray (#2F4F4F) is the closest CSS named color.

#173040 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #173040

Not just a swatch — here's how #173040 works with other colors. Named schemes with #173040 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #173040 Accent #A6C4C0 Surface #DEDABF Secondary #9AA0A0 Anchor #1F344A

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 #173040 Secondary #AEB4B8 Surface #F1F2F0 Support #7C93A6 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 #173040 Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #394F5F

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 #173040 Secondary #7F4439 Surface #E2DDC0 Accent #385245 Anchor #57233C

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 #173040 Secondary #4A5359 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 #173040 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 31/100

Low

Firm and assertive — carries weight and contrast.

Depth 67/100

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 28/100

Low

A faint retro warmth without tipping into sepia.

Luxury 69/100

High

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

Brand distinctiveness 16/100

Very low

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

UI accent fit 26/100

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 90/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #173040

For UI

For branding

For interior

For fashion

People also use #173040 with

Hunter Green Navy Bistre Platinum Charcoal

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 13.7:1. Use

Subtle surface Use #C6D8E3 for cards and hover fills. Tint 80

Avoid beside #172340 — 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 #173040 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: #173040;
  --color-base-rgb: 23 48 64;
  --color-base-oklch: oklch(29.7% 0.043 238.5);
  --color-50: #F3F8FB;
  --color-100: #E0EDF5;
  --color-200: #C3DBE9;
  --color-300: #99BFD6;
  --color-400: #72A2C0;
  --color-500: #5184A4;
  --color-600: #44687E;
  --color-700: #344C5A;
  --color-800: #25333C;
  --color-900: #182025;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  gunmetal-gray: {
    50: '#F3F8FB',
    100: '#E0EDF5',
    200: '#C3DBE9',
    300: '#99BFD6',
    400: '#72A2C0',
    500: '#5184A4',
    600: '#44687E',
    700: '#344C5A',
    800: '#25333C',
    900: '#182025',
  },
}

$base: #173040;
$base-ink: #FFFFFF;
$base-50: #F3F8FB;
$base-100: #E0EDF5;
$base-200: #C3DBE9;
$base-300: #99BFD6;
$base-400: #72A2C0;
$base-500: #5184A4;
$base-600: #44687E;
$base-700: #344C5A;
$base-800: #25333C;
$base-900: #182025;
$base-hover: #122633;
$base-subtle: #A9C5D6;

{
    "color": {
        "base": {
            "value": "#173040",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F8FB",
                "type": "color"
            },
            "100": {
                "value": "#E0EDF5",
                "type": "color"
            },
            "200": {
                "value": "#C3DBE9",
                "type": "color"
            },
            "300": {
                "value": "#99BFD6",
                "type": "color"
            },
            "400": {
                "value": "#72A2C0",
                "type": "color"
            },
            "500": {
                "value": "#5184A4",
                "type": "color"
            },
            "600": {
                "value": "#44687E",
                "type": "color"
            },
            "700": {
                "value": "#344C5A",
                "type": "color"
            },
            "800": {
                "value": "#25333C",
                "type": "color"
            },
            "900": {
                "value": "#182025",
                "type": "color"
            }
        }
    }
}