What color is #0A45A3?

#0A45A3 is a dark, vivid blue. In RGB it is rgb(10, 69, 163), and in HSL hsl(217, 88%, 34%).

Is #0A45A3 accessible as text?

On white, #0A45A3 has a contrast ratio of 8.78:1 (passes WCAG AA for body text); on black it is 2.39:1 (fails). For text placed on #0A45A3, use white for the best readability.

What is the closest Tailwind color to #0A45A3?

The nearest Tailwind CSS token is blue-800 (#193CB8).

What colors go well with #0A45A3?

#0A45A3 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #A3690A. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #0A45A3 below.

Is #0A45A3 good for buttons?

#0A45A3 works well for buttons and highlights, but use white text on #0A45A3 — black text only reaches 2.39:1, below the 4.5:1 needed for normal-size labels.

Is #0A45A3 the same as CSS darkslateblue?

No — #0A45A3 is not the CSS named color darkslateblue, but darkslateblue (#483D8B) is the closest CSS named color.

#0A45A3 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #0A45A3

Not just a swatch — here's how #0A45A3 works with other colors. Named schemes with #0A45A3 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #0A45A3 Accent #A5C4C1 Surface #DDDBBF Secondary #9AA0A1 Anchor #21344A

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

Tech Product Signal · 5 colors

Signal #0A45A3 Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #386BC2

Cobalt 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 Cobalt Blue.

Vintage Leather Lead · 5 colors

Lead #0A45A3 Secondary #7F4536 Surface #E1DDC1 Accent #375246 Anchor #57223A

Cobalt 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.

Berry & Cream Lead · 5 colors

Lead #0A45A3 Surface #F6E5D8 Anchor #5A2144 Accent #E4C2CA Secondary #322B2F

Cobalt Blue sits between cream and a deep berry here, softened by a blush accent and grounded by charcoal.

Minimal Editorial Surface · 5 colors

Surface #F6F4EF Accent #0A45A3 Secondary #617596 Support #9D8F88 Ink #16140F

Cobalt 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 Cobalt Blue carrying the quiet middle.

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Color Lab

How #0A45A3 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 8/100

Cool

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

Softness 31/100

Low

Firm and assertive — carries weight and contrast.

Depth 61/100

High

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

Naturalness 0/100

Very low

Reads engineered rather than organic — synthetic, digital.

Vintage feel 30/100

Low

A faint retro warmth without tipping into sepia.

Luxury 61/100

High

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

Brand distinctiveness 44/100

Moderate

Recognisable but shares space with nearby hues.

UI accent fit 79/100

High

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

Surface fit 13/100

Very low

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

Print safety 69/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #0A45A3

For UI

For branding

For interior

For fashion

People also use #0A45A3 with

Tiffany Blue Zaffre Olive Brown 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 8.8:1. Use

Subtle surface Use #C8D8F3 for cards and hover fills. Tint 80

Avoid beside #0A12A3 — 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 #0A45A3 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: #0A45A3;
  --color-base-rgb: 10 69 163;
  --color-base-oklch: oklch(41.9% 0.163 260.4);
  --color-50: #F0F6FE;
  --color-100: #D8E6FD;
  --color-200: #B2CEFA;
  --color-300: #7FAAF0;
  --color-400: #5088E2;
  --color-500: #2D68C8;
  --color-600: #2A5498;
  --color-700: #243F6B;
  --color-800: #1B2C46;
  --color-900: #131C2B;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  cobalt-blue: {
    50: '#F0F6FE',
    100: '#D8E6FD',
    200: '#B2CEFA',
    300: '#7FAAF0',
    400: '#5088E2',
    500: '#2D68C8',
    600: '#2A5498',
    700: '#243F6B',
    800: '#1B2C46',
    900: '#131C2B',
  },
}

$base: #0A45A3;
$base-ink: #FFFFFF;
$base-50: #F0F6FE;
$base-100: #D8E6FD;
$base-200: #B2CEFA;
$base-300: #7FAAF0;
$base-400: #5088E2;
$base-500: #2D68C8;
$base-600: #2A5498;
$base-700: #243F6B;
$base-800: #1B2C46;
$base-900: #131C2B;
$base-hover: #083782;
$base-subtle: #ABC5EE;

{
    "color": {
        "base": {
            "value": "#0A45A3",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F0F6FE",
                "type": "color"
            },
            "100": {
                "value": "#D8E6FD",
                "type": "color"
            },
            "200": {
                "value": "#B2CEFA",
                "type": "color"
            },
            "300": {
                "value": "#7FAAF0",
                "type": "color"
            },
            "400": {
                "value": "#5088E2",
                "type": "color"
            },
            "500": {
                "value": "#2D68C8",
                "type": "color"
            },
            "600": {
                "value": "#2A5498",
                "type": "color"
            },
            "700": {
                "value": "#243F6B",
                "type": "color"
            },
            "800": {
                "value": "#1B2C46",
                "type": "color"
            },
            "900": {
                "value": "#131C2B",
                "type": "color"
            }
        }
    }
}

Palettes built on #0A45A3

Color Lab

Pairs with #0A45A3

UI roles & guardrails

In real applications

Scales

Every model

Export