What color is #233B5B?

#233B5B is a dark blue. In RGB it is rgb(35, 59, 91), and in HSL hsl(214, 44%, 25%).

Is #233B5B accessible as text?

On white, #233B5B has a contrast ratio of 11.36:1 (passes WCAG AA for body text); on black it is 1.85:1 (fails). For text placed on #233B5B, use white for the best readability.

What is the closest Tailwind color to #233B5B?

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

What colors go well with #233B5B?

#233B5B pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #5C4324. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #233B5B below.

Is #233B5B good for buttons?

#233B5B works well for buttons and highlights, but use white text on #233B5B — black text only reaches 1.85:1, below the 4.5:1 needed for normal-size labels.

Is #233B5B the same as CSS darkslategray?

No — #233B5B is not the CSS named color darkslategray, but darkslategray (#2F4F4F) is the closest CSS named color.

#233B5B Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #233B5B

Not just a swatch — here's how #233B5B works with other colors. Named schemes with #233B5B in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #233B5B Accent #A5C4C1 Surface #DDDBBF Secondary #9AA0A1 Anchor #20344A

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 #233B5B 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 #233B5B Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #455C7B

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 #233B5B Secondary #7F4537 Surface #E1DDC1 Accent #375246 Anchor #57233B

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 #233B5B Secondary #58616D Support #9D8F89 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 #233B5B 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 33/100

Cool

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

Softness 34/100

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 37/100

Low

A faint retro warmth without tipping into sepia.

Luxury 67/100

High

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

Brand distinctiveness 25/100

Low

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

UI accent fit 45/100

Moderate

Workable accent with care around contrast.

Surface fit 43/100

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 #233B5B

For UI

For branding

For interior

For fashion

People also use #233B5B 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 11.4:1. Use

Subtle surface Use #CDD7E5 for cards and hover fills. Tint 80

Avoid beside #24295C — 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 #233B5B 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: #233B5B;
  --color-base-rgb: 35 59 91;
  --color-base-oklch: oklch(34.9% 0.064 256.0);
  --color-50: #F4F7FB;
  --color-100: #E1E9F4;
  --color-200: #C4D4E8;
  --color-300: #9BB4D4;
  --color-400: #7594BD;
  --color-500: #5475A1;
  --color-600: #465D7C;
  --color-700: #364559;
  --color-800: #262F3B;
  --color-900: #191E25;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  yale-blue: {
    50: '#F4F7FB',
    100: '#E1E9F4',
    200: '#C4D4E8',
    300: '#9BB4D4',
    400: '#7594BD',
    500: '#5475A1',
    600: '#465D7C',
    700: '#364559',
    800: '#262F3B',
    900: '#191E25',
  },
}

$base: #233B5B;
$base-ink: #FFFFFF;
$base-50: #F4F7FB;
$base-100: #E1E9F4;
$base-200: #C4D4E8;
$base-300: #9BB4D4;
$base-400: #7594BD;
$base-500: #5475A1;
$base-600: #465D7C;
$base-700: #364559;
$base-800: #262F3B;
$base-900: #191E25;
$base-hover: #1D3049;
$base-subtle: #B2C3D9;

{
    "color": {
        "base": {
            "value": "#233B5B",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F4F7FB",
                "type": "color"
            },
            "100": {
                "value": "#E1E9F4",
                "type": "color"
            },
            "200": {
                "value": "#C4D4E8",
                "type": "color"
            },
            "300": {
                "value": "#9BB4D4",
                "type": "color"
            },
            "400": {
                "value": "#7594BD",
                "type": "color"
            },
            "500": {
                "value": "#5475A1",
                "type": "color"
            },
            "600": {
                "value": "#465D7C",
                "type": "color"
            },
            "700": {
                "value": "#364559",
                "type": "color"
            },
            "800": {
                "value": "#262F3B",
                "type": "color"
            },
            "900": {
                "value": "#191E25",
                "type": "color"
            }
        }
    }
}