What color is #233B64?

#233B64 is a dark blue. In RGB it is rgb(35, 59, 100), and in HSL hsl(218, 48%, 26%).

Is #233B64 accessible as text?

On white, #233B64 has a contrast ratio of 11.16:1 (passes WCAG AA for body text); on black it is 1.88:1 (fails). For text placed on #233B64, use white for the best readability.

What is the closest Tailwind color to #233B64?

The nearest Tailwind CSS token is sky-900 (#024A70).

What colors go well with #233B64?

#233B64 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #624B22. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #233B64 below.

Is #233B64 good for buttons?

#233B64 works well for buttons and highlights, but use white text on #233B64 — black text only reaches 1.88:1, below the 4.5:1 needed for normal-size labels.

Is #233B64 the same as CSS darkslategray?

No — #233B64 is not the CSS named color darkslategray, but darkslategray (#2F4F4F) is the closest CSS named color.

#233B64 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #233B64

Not just a swatch — here's how #233B64 works with other colors. Named schemes with #233B64 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #233B64 Accent #A5C4C1 Surface #DDDBBF 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.

Nordic Calm Accent · 5 colors

Accent #233B64 Secondary #AEB4B8 Surface #F1F2F0 Support #7D93A6 Anchor #2E3236

Yale 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 #233B64 Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #455C84

Yale 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 Yale Blue.

Vintage Leather Lead · 5 colors

Lead #233B64 Secondary #7F4536 Surface #E1DDC1 Accent #375246 Anchor #57223A

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 #F6F4EF Accent #233B64 Secondary #596272 Support #9D8F88 Ink #16140F

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 #233B64 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 30/100

Cool

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

Softness 33/100

Low

Middle-weight — neither delicate nor heavy.

Depth 63/100

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 42/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 68/100

High

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

Brand distinctiveness 30/100

Low

Recognisable but shares space with nearby hues.

UI accent fit 50/100

Moderate

Workable accent with care around contrast.

Surface fit 38/100

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 #233B64

For UI

For branding

For interior

For fashion

People also use #233B64 with

Myrtle Green Russian Violet Sepia Gainsboro 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 11.2:1. Use

Subtle surface Use #CCD6E6 for cards and hover fills. Tint 80

Avoid beside #222562 — 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 #233B64 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: #233B64;
  --color-base-rgb: 35 59 100;
  --color-base-oklch: oklch(35.5% 0.078 260.5);
  --color-50: #F3F6FB;
  --color-100: #E0E8F5;
  --color-200: #C3D1EA;
  --color-300: #99AFD7;
  --color-400: #718EC1;
  --color-500: #506FA5;
  --color-600: #43597F;
  --color-700: #34425B;
  --color-800: #252D3C;
  --color-900: #181D25;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  yale-blue: {
    50: '#F3F6FB',
    100: '#E0E8F5',
    200: '#C3D1EA',
    300: '#99AFD7',
    400: '#718EC1',
    500: '#506FA5',
    600: '#43597F',
    700: '#34425B',
    800: '#252D3C',
    900: '#181D25',
  },
}

$base: #233B64;
$base-ink: #FFFFFF;
$base-50: #F3F6FB;
$base-100: #E0E8F5;
$base-200: #C3D1EA;
$base-300: #99AFD7;
$base-400: #718EC1;
$base-500: #506FA5;
$base-600: #43597F;
$base-700: #34425B;
$base-800: #252D3C;
$base-900: #181D25;
$base-hover: #1C2E4E;
$base-subtle: #B2C1DB;

{
    "color": {
        "base": {
            "value": "#233B64",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F6FB",
                "type": "color"
            },
            "100": {
                "value": "#E0E8F5",
                "type": "color"
            },
            "200": {
                "value": "#C3D1EA",
                "type": "color"
            },
            "300": {
                "value": "#99AFD7",
                "type": "color"
            },
            "400": {
                "value": "#718EC1",
                "type": "color"
            },
            "500": {
                "value": "#506FA5",
                "type": "color"
            },
            "600": {
                "value": "#43597F",
                "type": "color"
            },
            "700": {
                "value": "#34425B",
                "type": "color"
            },
            "800": {
                "value": "#252D3C",
                "type": "color"
            },
            "900": {
                "value": "#181D25",
                "type": "color"
            }
        }
    }
}