What color is #3F73CB?

#3F73CB is a medium blue. In RGB it is rgb(63, 115, 203), and in HSL hsl(218, 57%, 52%).

Is #3F73CB accessible as text?

On white, #3F73CB has a contrast ratio of 4.64:1 (passes WCAG AA for body text); on black it is 4.53:1 (passes). For text placed on #3F73CB, use white for the best readability.

What is the closest Tailwind color to #3F73CB?

The nearest Tailwind CSS token is sky-600 (#0084D1).

What colors go well with #3F73CB?

#3F73CB pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #CA973F. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #3F73CB below.

Is #3F73CB good for buttons?

#3F73CB works for buttons; white text has the higher contrast, so prefer it for labels.

Is #3F73CB the same as CSS royalblue?

No — #3F73CB is not the CSS named color royalblue, but royalblue (#4169E1) is the closest CSS named color.

#3F73CB Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #3F73CB

Not just a swatch — here's how #3F73CB works with other colors. Named schemes with #3F73CB in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #3F73CB Accent #A5C4C1 Surface #DDDBBF Secondary #9AA0A1 Anchor #21344A

True 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 #3F73CB Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #6899EB

True 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 True Blue.

Vintage Leather Lead · 5 colors

Lead #3F73CB Secondary #7F4536 Surface #E1DDC1 Accent #375246 Anchor #57223A

True 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 #3F73CB Surface #F6E5D8 Anchor #5A2144 Accent #E4C2CA Secondary #322B2F

True 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 #3F73CB Secondary #8DA1C1 Support #9D8F88 Ink #16140F

True 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 True Blue carrying the quiet middle.

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Color Lab

How #3F73CB 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 42/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 45/100

Moderate

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

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 49/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 40/100

Low

Recognisable but shares space with nearby hues.

UI accent fit 98/100

Very high

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

Surface fit 14/100

Very low

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

Print safety 71/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #3F73CB

For UI

For branding

For interior

For fashion

People also use #3F73CB with

Medium Turquoise Slate Blue Caramel Gainsboro Charcoal

UI roles & guardrails

Primary action Safe as a filled button with white label. AA

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 4.6:1. Use

Subtle surface Use #DCE4F1 for cards and hover fills. Tint 80

Avoid beside #3F43CA — 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 #3F73CB at work across the surfaces designers actually ship.

Website / UI

Northwind Sign up

Build faster.

A working theme, generated in seconds.

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: #3F73CB;
  --color-base-rgb: 63 115 203;
  --color-base-oklch: oklch(56.4% 0.147 260.2);
  --color-50: #F3F6FC;
  --color-100: #DEE7F7;
  --color-200: #BFD0ED;
  --color-300: #93AEDC;
  --color-400: #6A8CC8;
  --color-500: #486DAD;
  --color-600: #3D5784;
  --color-700: #30415E;
  --color-800: #232D3E;
  --color-900: #171D26;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  true-blue: {
    50: '#F3F6FC',
    100: '#DEE7F7',
    200: '#BFD0ED',
    300: '#93AEDC',
    400: '#6A8CC8',
    500: '#486DAD',
    600: '#3D5784',
    700: '#30415E',
    800: '#232D3E',
    900: '#171D26',
  },
}

$base: #3F73CB;
$base-ink: #FFFFFF;
$base-50: #F3F6FC;
$base-100: #DEE7F7;
$base-200: #BFD0ED;
$base-300: #93AEDC;
$base-400: #6A8CC8;
$base-500: #486DAD;
$base-600: #3D5784;
$base-700: #30415E;
$base-800: #232D3E;
$base-900: #171D26;
$base-hover: #2E5AA7;
$base-subtle: #CAD6EA;

{
    "color": {
        "base": {
            "value": "#3F73CB",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F6FC",
                "type": "color"
            },
            "100": {
                "value": "#DEE7F7",
                "type": "color"
            },
            "200": {
                "value": "#BFD0ED",
                "type": "color"
            },
            "300": {
                "value": "#93AEDC",
                "type": "color"
            },
            "400": {
                "value": "#6A8CC8",
                "type": "color"
            },
            "500": {
                "value": "#486DAD",
                "type": "color"
            },
            "600": {
                "value": "#3D5784",
                "type": "color"
            },
            "700": {
                "value": "#30415E",
                "type": "color"
            },
            "800": {
                "value": "#232D3E",
                "type": "color"
            },
            "900": {
                "value": "#171D26",
                "type": "color"
            }
        }
    }
}

Palettes built on #3F73CB

Color Lab

Pairs with #3F73CB

UI roles & guardrails

In real applications

Scales

Every model

Export