What color is #1503BB?

#1503BB is a dark, vivid indigo. In RGB it is rgb(21, 3, 187), and in HSL hsl(246, 97%, 37%).

Is #1503BB accessible as text?

On white, #1503BB has a contrast ratio of 11.92:1 (passes WCAG AA for body text); on black it is 1.76:1 (fails). For text placed on #1503BB, use white for the best readability.

What is the closest Tailwind color to #1503BB?

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

What colors go well with #1503BB?

#1503BB pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #A8BA03. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #1503BB below.

Is #1503BB good for buttons?

#1503BB works well for buttons and highlights, but use white text on #1503BB — black text only reaches 1.76:1, below the 4.5:1 needed for normal-size labels.

Is #1503BB the same as CSS mediumblue?

No — #1503BB is not the CSS named color mediumblue, but mediumblue (#0000CD) is the closest CSS named color.

#1503BB Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #1503BB

Not just a swatch — here's how #1503BB works with other colors. Named schemes with #1503BB in its natural role, and a note on why the supporting colors balance it.

Luxury Packaging Feature · 5 colors

Feature #1503BB Anchor #141210 Accent #DD965A Secondary #242933 Surface #F4ECE3

Medium 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 #1503BB Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #2A4AD8

Medium 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 Medium Blue.

Moody Editorial Color · 5 colors

Color #1503BB Anchor #2A2A2E Secondary #6E6E74 Surface #EEE5DB Accent #23006B

Medium 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 Medium Blue.

Coastal Morning Lead · 5 colors

Lead #1503BB Accent #A5C4C2 Surface #EAD5C0 Secondary #9AA0A1 Anchor #21344A

Medium 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 #1503BB Secondary #4F6396 Support #9D8F88 Ink #18140F

Medium 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 Medium Blue carrying the quiet middle.

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Color Lab

How #1503BB 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 10/100

Cool

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

Softness 20/100

Low

Firm and assertive — carries weight and contrast.

Depth 70/100

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 8/100

Very low

Clean and current — no dusty, aged cast.

Luxury 58/100

Moderate

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

Brand distinctiveness 94/100

Very high

Bold and ownable — memorable as a primary brand color.

UI accent fit 41/100

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 57/100

Moderate

Prints close, with a slight loss of vibrancy.

Pairs with #1503BB

For UI

For branding

For interior

For fashion

People also use #1503BB with

Royal 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 11.9:1. Use

Subtle surface Use #CDC8F5 for cards and hover fills. Tint 80

Avoid beside #5203BA — 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 #1503BB 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: #1503BB;
  --color-base-rgb: 21 3 187;
  --color-base-oklch: oklch(36.5% 0.243 267.2);
  --color-50: #F2F0FE;
  --color-100: #DCD8FD;
  --color-200: #B8B1FC;
  --color-300: #8679F6;
  --color-400: #5949E9;
  --color-500: #3625D0;
  --color-600: #31259D;
  --color-700: #28206F;
  --color-800: #1E1948;
  --color-900: #14112C;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  medium-blue: {
    50: '#F2F0FE',
    100: '#DCD8FD',
    200: '#B8B1FC',
    300: '#8679F6',
    400: '#5949E9',
    500: '#3625D0',
    600: '#31259D',
    700: '#28206F',
    800: '#1E1948',
    900: '#14112C',
  },
}

$base: #1503BB;
$base-ink: #FFFFFF;
$base-50: #F2F0FE;
$base-100: #DCD8FD;
$base-200: #B8B1FC;
$base-300: #8679F6;
$base-400: #5949E9;
$base-500: #3625D0;
$base-600: #31259D;
$base-700: #28206F;
$base-800: #1E1948;
$base-900: #14112C;
$base-hover: #110295;
$base-subtle: #B2ABF2;

{
    "color": {
        "base": {
            "value": "#1503BB",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F2F0FE",
                "type": "color"
            },
            "100": {
                "value": "#DCD8FD",
                "type": "color"
            },
            "200": {
                "value": "#B8B1FC",
                "type": "color"
            },
            "300": {
                "value": "#8679F6",
                "type": "color"
            },
            "400": {
                "value": "#5949E9",
                "type": "color"
            },
            "500": {
                "value": "#3625D0",
                "type": "color"
            },
            "600": {
                "value": "#31259D",
                "type": "color"
            },
            "700": {
                "value": "#28206F",
                "type": "color"
            },
            "800": {
                "value": "#1E1948",
                "type": "color"
            },
            "900": {
                "value": "#14112C",
                "type": "color"
            }
        }
    }
}

Palettes built on #1503BB

Color Lab

Pairs with #1503BB

UI roles & guardrails

In real applications

Scales

Every model

Export