What color is #4209DF?

#4209DF is a medium, vivid indigo. In RGB it is rgb(66, 9, 223), and in HSL hsl(256, 92%, 45%).

Is #4209DF accessible as text?

On white, #4209DF has a contrast ratio of 8.99:1 (passes WCAG AA for body text); on black it is 2.34:1 (fails). For text placed on #4209DF, use white for the best readability.

What is the closest Tailwind color to #4209DF?

The nearest Tailwind CSS token is indigo-700 (#432DD7).

What colors go well with #4209DF?

#4209DF pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #A4DC09. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #4209DF below.

Is #4209DF good for buttons?

#4209DF works well for buttons and highlights, but use white text on #4209DF — black text only reaches 2.34:1, below the 4.5:1 needed for normal-size labels.

Is #4209DF the same as CSS blue?

No — #4209DF is not the CSS named color blue, but blue (#0000FF) is the closest CSS named color by perceptual color distance — it sits in a different color family, so treat it as a rough reference, not a match.

#4209DF Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #4209DF

Not just a swatch — here's how #4209DF works with other colors. Named schemes with #4209DF in its natural role, and a note on why the supporting colors balance it.

Tech Product Signal · 5 colors

Signal #4209DF Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #5B54FC

Ultramarine is the vivid signal in this product UI — on a near-black surface with cool white, a slate grey and a lighter tint of Ultramarine.

Berry & Cream Lead · 5 colors

Lead #4209DF Surface #F6E5D8 Anchor #5B2142 Accent #E5C2C9 Secondary #322B2F

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

Minimal Editorial Surface · 5 colors

Surface #F8F4EF Accent #4209DF Secondary #6C74B1 Support #9D9088 Ink #18140F

Ultramarine 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 Ultramarine carrying the quiet middle.

Coastal Morning Lead · 5 colors

Lead #4209DF Accent #A5C4C2 Surface #EAD5BF Secondary #9AA0A1 Anchor #22344A

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

Sunset Warmth Glow · 5 colors

Glow #4209DF Secondary #E86A71 Accent #F6934E Anchor #583B57 Surface #F7E7D7

Ultramarine glows at the center of this sunset palette, joined by coral and gold, deepened by a plum anchor and cooled with cream.

Build a working theme in the generator →

Color Lab

How #4209DF 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 16/100

Cool

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

Softness 22/100

Low

Firm and assertive — carries weight and contrast.

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 2/100

Very low

Clean and current — no dusty, aged cast.

Luxury 51/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 100/100

Very high

Bold and ownable — memorable as a primary brand color.

UI accent fit 45/100

Moderate

Workable accent with care around contrast.

Surface fit 11/100

Very low

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

Print safety 58/100

Moderate

Prints close, with a slight loss of vibrancy.

Pairs with #4209DF

For UI

For branding

For interior

For fashion

People also use #4209DF with

Neon Blue Electric Purple Peridot Gainsboro Russian Violet

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 9.0:1. Use

Subtle surface Use #DAD0F6 for cards and hover fills. Tint 80

Avoid beside #8809DC — 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 #4209DF 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: #4209DF;
  --color-base-rgb: 66 9 223;
  --color-base-oklch: oklch(43.9% 0.267 277.3);
  --color-50: #F4F0FE;
  --color-100: #E2D8FD;
  --color-200: #C5B1FC;
  --color-300: #9C7CF3;
  --color-400: #754DE5;
  --color-500: #5529CB;
  --color-600: #46289A;
  --color-700: #36226D;
  --color-800: #261A47;
  --color-900: #19122B;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  ultramarine: {
    50: '#F4F0FE',
    100: '#E2D8FD',
    200: '#C5B1FC',
    300: '#9C7CF3',
    400: '#754DE5',
    500: '#5529CB',
    600: '#46289A',
    700: '#36226D',
    800: '#261A47',
    900: '#19122B',
  },
}

$base: #4209DF;
$base-ink: #FFFFFF;
$base-50: #F4F0FE;
$base-100: #E2D8FD;
$base-200: #C5B1FC;
$base-300: #9C7CF3;
$base-400: #754DE5;
$base-500: #5529CB;
$base-600: #46289A;
$base-700: #36226D;
$base-800: #261A47;
$base-900: #19122B;
$base-hover: #3407B0;
$base-subtle: #C7B8F2;

{
    "color": {
        "base": {
            "value": "#4209DF",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F4F0FE",
                "type": "color"
            },
            "100": {
                "value": "#E2D8FD",
                "type": "color"
            },
            "200": {
                "value": "#C5B1FC",
                "type": "color"
            },
            "300": {
                "value": "#9C7CF3",
                "type": "color"
            },
            "400": {
                "value": "#754DE5",
                "type": "color"
            },
            "500": {
                "value": "#5529CB",
                "type": "color"
            },
            "600": {
                "value": "#46289A",
                "type": "color"
            },
            "700": {
                "value": "#36226D",
                "type": "color"
            },
            "800": {
                "value": "#261A47",
                "type": "color"
            },
            "900": {
                "value": "#19122B",
                "type": "color"
            }
        }
    }
}

Palettes built on #4209DF

Color Lab

Pairs with #4209DF

UI roles & guardrails

In real applications

Scales

Every model

Export