What color is #231CB0?

#231CB0 is a medium, vivid blue. In RGB it is rgb(35, 28, 176), and in HSL hsl(243, 73%, 40%).

Is #231CB0 accessible as text?

On white, #231CB0 has a contrast ratio of 11.26:1 (passes WCAG AA for body text); on black it is 1.86:1 (fails). For text placed on #231CB0, use white for the best readability.

What is the closest Tailwind color to #231CB0?

The nearest Tailwind CSS token is indigo-800 (#372AAC).

What colors go well with #231CB0?

#231CB0 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #A9B01C. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #231CB0 below.

Is #231CB0 good for buttons?

#231CB0 works well for buttons and highlights, but use white text on #231CB0 — black text only reaches 1.86:1, below the 4.5:1 needed for normal-size labels.

Is #231CB0 the same as CSS mediumblue?

No — #231CB0 is not the CSS named color mediumblue, but mediumblue (#0000CD) is the closest CSS named color.

#231CB0 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #231CB0

Not just a swatch — here's how #231CB0 works with other colors. Named schemes with #231CB0 in its natural role, and a note on why the supporting colors balance it.

Luxury Packaging Feature · 5 colors

Feature #231CB0 Anchor #141210 Accent #DC9659 Secondary #252833 Surface #F3ECE3

Klein Blue carries the depth in this luxury scheme, offset by a brass accent and near-black and held together by a deep neutral and an off-white surface.

Tech Product Signal · 5 colors

Signal #231CB0 Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #3D4FCE

Klein 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 Klein Blue.

Moody Editorial Color · 5 colors

Color #231CB0 Anchor #2A2A2E Secondary #6E6E74 Surface #EEE5DB Accent #270064

Klein Blue adds the colour to this moody editorial scheme — charcoal and a mid-grey around it, a bone highlight, and a muted jewel accent drawn from Klein Blue.

Coastal Morning Lead · 5 colors

Lead #231CB0 Accent #A5C4C2 Surface #EAD5C0 Secondary #9AA0A1 Anchor #21344A

Klein Blue opens this coastal palette with sea-glass and warm sand alongside it, grounded by driftwood grey and a deep-navy anchor.

Minimal Editorial Surface · 5 colors

Surface #F8F4EF Accent #231CB0 Secondary #576593 Support #9D8F88 Ink #18140F

Klein 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 Klein Blue carrying the quiet middle.

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Color Lab

How #231CB0 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 12/100

Cool

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

Softness 23/100

Low

Firm and assertive — carries weight and contrast.

Depth 68/100

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 15/100

Very low

Clean and current — no dusty, aged cast.

Luxury 60/100

Moderate

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

Brand distinctiveness 84/100

Very high

Bold and ownable — memorable as a primary brand color.

UI accent fit 52/100

Moderate

Workable accent with care around contrast.

Surface fit 16/100

Very low

Too saturated or mid-toned for big areas — keep it to accents.

Print safety 63/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #231CB0

For UI

For branding

For interior

For fashion

People also use #231CB0 with

True Blue Grape Citron Gainsboro Prussian Blue

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 11.3:1. Use

Subtle surface Use #D2D0F0 for cards and hover fills. Tint 80

Avoid beside #551CB0 — 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 #231CB0 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: #231CB0;
  --color-base-rgb: 35 28 176;
  --color-base-oklch: oklch(37.4% 0.216 271.0);
  --color-50: #F2F1FD;
  --color-100: #DCDBFA;
  --color-200: #BBB9F4;
  --color-300: #8D88E7;
  --color-400: #635DD5;
  --color-500: #413ABB;
  --color-600: #38338E;
  --color-700: #2D2A65;
  --color-800: #211F42;
  --color-900: #161528;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  klein-blue: {
    50: '#F2F1FD',
    100: '#DCDBFA',
    200: '#BBB9F4',
    300: '#8D88E7',
    400: '#635DD5',
    500: '#413ABB',
    600: '#38338E',
    700: '#2D2A65',
    800: '#211F42',
    900: '#161528',
  },
}

$base: #231CB0;
$base-ink: #FFFFFF;
$base-50: #F2F1FD;
$base-100: #DCDBFA;
$base-200: #BBB9F4;
$base-300: #8D88E7;
$base-400: #635DD5;
$base-500: #413ABB;
$base-600: #38338E;
$base-700: #2D2A65;
$base-800: #211F42;
$base-900: #161528;
$base-hover: #1C168D;
$base-subtle: #BAB8EB;

{
    "color": {
        "base": {
            "value": "#231CB0",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F2F1FD",
                "type": "color"
            },
            "100": {
                "value": "#DCDBFA",
                "type": "color"
            },
            "200": {
                "value": "#BBB9F4",
                "type": "color"
            },
            "300": {
                "value": "#8D88E7",
                "type": "color"
            },
            "400": {
                "value": "#635DD5",
                "type": "color"
            },
            "500": {
                "value": "#413ABB",
                "type": "color"
            },
            "600": {
                "value": "#38338E",
                "type": "color"
            },
            "700": {
                "value": "#2D2A65",
                "type": "color"
            },
            "800": {
                "value": "#211F42",
                "type": "color"
            },
            "900": {
                "value": "#161528",
                "type": "color"
            }
        }
    }
}

Palettes built on #231CB0

Color Lab

Pairs with #231CB0

UI roles & guardrails

In real applications

Scales

Every model

Export