What color is #005240?

#005240 is a very dark, vivid teal. In RGB it is rgb(0, 82, 64), and in HSL hsl(167, 100%, 16%).

Is #005240 accessible as text?

On white, #005240 has a contrast ratio of 9.21:1 (passes WCAG AA for body text); on black it is 2.28:1 (fails). For text placed on #005240, use white for the best readability.

What is the closest Tailwind color to #005240?

The nearest Tailwind CSS token is emerald-900 (#004F3B).

What colors go well with #005240?

#005240 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #520012. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #005240 below.

Is #005240 good for buttons?

#005240 works well for buttons and highlights, but use white text on #005240 — black text only reaches 2.28:1, below the 4.5:1 needed for normal-size labels.

Is #005240 the same as CSS darkslategray?

No — #005240 is not the CSS named color darkslategray, but darkslategray (#2F4F4F) is the closest CSS named color by perceptual color distance — it sits in a different color family, so treat it as a rough reference, not a match.

#005240 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #005240

Not just a swatch — here's how #005240 works with other colors. Named schemes with #005240 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #005240 Accent #A7C4BC Surface #E1D9BE Secondary #9AA0A0 Anchor #1B3549

Castleton Green 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 #005240 Secondary #ADB4B7 Surface #F1F2F0 Support #7994A4 Anchor #2D3236

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

Vintage Leather Lead · 5 colors

Lead #005240 Secondary #734F19 Surface #E5DBC0 Accent #3B5141 Anchor #5B231F

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

Modern Café Dominant · 5 colors

Dominant #005240 Anchor #382B1E Surface #ECE4D0 Accent #849C6F Secondary #3A3833

Castleton Green anchors this café scheme as the warm mid-tone, lifted by latte cream and a muted sage accent and grounded by espresso brown and a warm charcoal.

Minimal Editorial Surface · 5 colors

Surface #F7F4EF Accent #005240 Secondary #5D716A Support #989286 Ink #16140F

Castleton Green 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 Castleton Green carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #005240 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 38/100

Neutral

Balanced temperature — flexible, sits between warm and cool schemes.

Softness 36/100

Low

Middle-weight — neither delicate nor heavy.

Depth 60/100

Moderate

Mid depth — usable as an accent or a muted ground.

Naturalness 47/100

Moderate

Loosely natural — an earthy edge without being rustic.

Vintage feel 49/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 64/100

High

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

Brand distinctiveness 21/100

Low

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

UI accent fit 60/100

High

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

Surface fit 36/100

Low

Usable as a tinted surface in measured doses.

Print safety 85/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #005240

For UI

For branding

For interior

For fashion

People also use #005240 with

Green Prussian Blue 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 9.2:1. Use

Subtle surface Use #B5F3E6 for cards and hover fills. Tint 80

Avoid beside #004852 — 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 #005240 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: #005240;
  --color-base-rgb: 0 82 64;
  --color-base-oklch: oklch(39.1% 0.076 171.5);
  --color-50: #F0FEFB;
  --color-100: #D8FDF5;
  --color-200: #B1FCEB;
  --color-300: #77F8DC;
  --color-400: #46ECC8;
  --color-500: #22D2AC;
  --color-600: #239F84;
  --color-700: #1F705E;
  --color-800: #18483E;
  --color-900: #112C26;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  castleton-green: {
    50: '#F0FEFB',
    100: '#D8FDF5',
    200: '#B1FCEB',
    300: '#77F8DC',
    400: '#46ECC8',
    500: '#22D2AC',
    600: '#239F84',
    700: '#1F705E',
    800: '#18483E',
    900: '#112C26',
  },
}

$base: #005240;
$base-ink: #FFFFFF;
$base-50: #F0FEFB;
$base-100: #D8FDF5;
$base-200: #B1FCEB;
$base-300: #77F8DC;
$base-400: #46ECC8;
$base-500: #22D2AC;
$base-600: #239F84;
$base-700: #1F705E;
$base-800: #18483E;
$base-900: #112C26;
$base-hover: #004133;
$base-subtle: #8EF0DA;

{
    "color": {
        "base": {
            "value": "#005240",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F0FEFB",
                "type": "color"
            },
            "100": {
                "value": "#D8FDF5",
                "type": "color"
            },
            "200": {
                "value": "#B1FCEB",
                "type": "color"
            },
            "300": {
                "value": "#77F8DC",
                "type": "color"
            },
            "400": {
                "value": "#46ECC8",
                "type": "color"
            },
            "500": {
                "value": "#22D2AC",
                "type": "color"
            },
            "600": {
                "value": "#239F84",
                "type": "color"
            },
            "700": {
                "value": "#1F705E",
                "type": "color"
            },
            "800": {
                "value": "#18483E",
                "type": "color"
            },
            "900": {
                "value": "#112C26",
                "type": "color"
            }
        }
    }
}

Palettes built on #005240

Color Lab

Pairs with #005240

UI roles & guardrails

In real applications

Scales

Every model

Export