What color is #331EF6?

#331EF6 is a medium, vivid indigo. In RGB it is rgb(51, 30, 246), and in HSL hsl(246, 92%, 54%).

Is #331EF6 accessible as text?

On white, #331EF6 has a contrast ratio of 7.90:1 (passes WCAG AA for body text); on black it is 2.66:1 (fails). For text placed on #331EF6, use white for the best readability.

What is the closest Tailwind color to #331EF6?

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

What colors go well with #331EF6?

#331EF6 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #E0F61E. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #331EF6 below.

Is #331EF6 good for buttons?

#331EF6 works well for buttons and highlights, but use white text on #331EF6 — black text only reaches 2.66:1, below the 4.5:1 needed for normal-size labels.

Is #331EF6 the same as CSS blue?

No — #331EF6 is not the CSS named color blue, but blue (#0000FF) is the closest CSS named color.

#331EF6 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #331EF6

Not just a swatch — here's how #331EF6 works with other colors. Named schemes with #331EF6 in its natural role, and a note on why the supporting colors balance it.

Tech Product Signal · 5 colors

Signal #331EF6 Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #4C60FF

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.

Coastal Morning Lead · 5 colors

Lead #331EF6 Accent #A5C4C2 Surface #EAD5C0 Secondary #9AA0A1 Anchor #21344A

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

Berry & Cream Lead · 5 colors

Lead #331EF6 Surface #F6E5D8 Anchor #5B2143 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 #331EF6 Secondary #6C7FBF Support #9D8F88 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.

Sunset Warmth Glow · 5 colors

Glow #331EF6 Secondary #E86A73 Accent #F6924F Anchor #573B58 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 #331EF6 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 21/100

Low

Firm and assertive — carries weight and contrast.

Depth 60/100

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 0/100

Very low

Clean and current — no dusty, aged cast.

Luxury 47/100

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 40/100

Low

Workable accent with care around contrast.

Surface fit 10/100

Very low

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

Print safety 52/100

Moderate

Prints close, with a slight loss of vibrancy.

Pairs with #331EF6

For UI

For branding

For interior

For fashion

People also use #331EF6 with

Cornflower Blue Electric Purple Pear 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 7.9:1. Use

Subtle surface Use #DBD8F7 for cards and hover fills. Tint 80

Avoid beside #7B1EF6 — 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 #331EF6 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: #331EF6;
  --color-base-rgb: 51 30 246;
  --color-base-oklch: oklch(46.8% 0.286 270.9);
  --color-50: #F2F0FE;
  --color-100: #DCD8FD;
  --color-200: #B8B1FC;
  --color-300: #887CF3;
  --color-400: #5C4DE5;
  --color-500: #3A29CB;
  --color-600: #33289A;
  --color-700: #2A226D;
  --color-800: #1F1A47;
  --color-900: #15122B;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  ultramarine: {
    50: '#F2F0FE',
    100: '#DCD8FD',
    200: '#B8B1FC',
    300: '#887CF3',
    400: '#5C4DE5',
    500: '#3A29CB',
    600: '#33289A',
    700: '#2A226D',
    800: '#1F1A47',
    900: '#15122B',
  },
}

$base: #331EF6;
$base-ink: #FFFFFF;
$base-50: #F2F0FE;
$base-100: #DCD8FD;
$base-200: #B8B1FC;
$base-300: #887CF3;
$base-400: #5C4DE5;
$base-500: #3A29CB;
$base-600: #33289A;
$base-700: #2A226D;
$base-800: #1F1A47;
$base-900: #15122B;
$base-hover: #1D09D4;
$base-subtle: #C8C3F4;

{
    "color": {
        "base": {
            "value": "#331EF6",
            "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": "#887CF3",
                "type": "color"
            },
            "400": {
                "value": "#5C4DE5",
                "type": "color"
            },
            "500": {
                "value": "#3A29CB",
                "type": "color"
            },
            "600": {
                "value": "#33289A",
                "type": "color"
            },
            "700": {
                "value": "#2A226D",
                "type": "color"
            },
            "800": {
                "value": "#1F1A47",
                "type": "color"
            },
            "900": {
                "value": "#15122B",
                "type": "color"
            }
        }
    }
}

Palettes built on #331EF6

Color Lab

Pairs with #331EF6

UI roles & guardrails

In real applications

Scales

Every model

Export