What color is #100331?

#100331 is a very dark, vivid indigo. In RGB it is rgb(16, 3, 49), and in HSL hsl(257, 88%, 10%).

Is #100331 accessible as text?

On white, #100331 has a contrast ratio of 19.46:1 (passes WCAG AA for body text); on black it is 1.08:1 (fails). For text placed on #100331, use white for the best readability.

What is the closest Tailwind color to #100331?

The nearest Tailwind CSS token is mauve-950 (#0C090C).

What colors go well with #100331?

#100331 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #233003. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #100331 below.

Is #100331 good for buttons?

#100331 works well for buttons and highlights, but use white text on #100331 — black text only reaches 1.08:1, below the 4.5:1 needed for normal-size labels.

Is #100331 the same as CSS midnightblue?

No — #100331 is not the CSS named color midnightblue, but midnightblue (#191970) 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.

#100331 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #100331

Not just a swatch — here's how #100331 works with other colors. Named schemes with #100331 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #100331 Accent #A5C4C3 Surface #E9D6BF Secondary #9AA0A1 Anchor #22334A

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

Nordic Calm Accent · 5 colors

Accent #100331 Secondary #AFB4B8 Surface #F1F2F0 Support #7E92A7 Anchor #2E3236

Jet Black keeps this Nordic scheme quiet — cool greys and a soft white around it, a muted-blue support and a charcoal anchor.

Vintage Leather Lead · 5 colors

Lead #100331 Secondary #7E4633 Surface #EDD8C2 Accent #365247 Anchor #582238

Jet Black plays the worn-leather lead, deepened by saddle brown and an oxblood anchor, softened by aged cream and cooled by a muted forest green.

Luxury Packaging Feature · 5 colors

Feature #100331 Anchor #141210 Accent #DB9757 Secondary #282732 Surface #F3ECE3

Jet Black 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.

Minimal Editorial Surface · 5 colors

Surface #F8F4EF Accent #100331 Secondary #2F2E3F Support #9D9088 Ink #18140F

Jet Black 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 Jet Black carrying the quiet middle.

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Color Lab

How #100331 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 36/100

Cool

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

Softness 17/100

Very low

Firm and assertive — carries weight and contrast.

Depth 82/100

Very 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 29/100

Low

A faint retro warmth without tipping into sepia.

Luxury 84/100

Very high

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

Brand distinctiveness 33/100

Low

Recognisable but shares space with nearby hues.

UI accent fit 9/100

Very low

Weak as an action color — too pale, too dark or too muted to signal.

Surface fit 48/100

Moderate

Usable as a tinted surface in measured doses.

Print safety 88/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #100331

For UI

For branding

For interior

For fashion

People also use #100331 with

Navy Deep Purple Sacramento Green 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 19.5:1. Use

Subtle surface Use #C4B4EE for cards and hover fills. Tint 80

Avoid beside #1F0330 — 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 #100331 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: #100331;
  --color-base-rgb: 16 3 49;
  --color-base-oklch: oklch(16.9% 0.086 287.6);
  --color-50: #F4F0FE;
  --color-100: #E2D8FD;
  --color-200: #C7B2FA;
  --color-300: #9F7FF0;
  --color-400: #7950E2;
  --color-500: #592DC8;
  --color-600: #492A98;
  --color-700: #38246B;
  --color-800: #271B46;
  --color-900: #19132B;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  jet-black: {
    50: '#F4F0FE',
    100: '#E2D8FD',
    200: '#C7B2FA',
    300: '#9F7FF0',
    400: '#7950E2',
    500: '#592DC8',
    600: '#492A98',
    700: '#38246B',
    800: '#271B46',
    900: '#19132B',
  },
}

$base: #100331;
$base-ink: #FFFFFF;
$base-50: #F4F0FE;
$base-100: #E2D8FD;
$base-200: #C7B2FA;
$base-300: #9F7FF0;
$base-400: #7950E2;
$base-500: #592DC8;
$base-600: #492A98;
$base-700: #38246B;
$base-800: #271B46;
$base-900: #19132B;
$base-hover: #0D0226;
$base-subtle: #A68CE8;

{
    "color": {
        "base": {
            "value": "#100331",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F4F0FE",
                "type": "color"
            },
            "100": {
                "value": "#E2D8FD",
                "type": "color"
            },
            "200": {
                "value": "#C7B2FA",
                "type": "color"
            },
            "300": {
                "value": "#9F7FF0",
                "type": "color"
            },
            "400": {
                "value": "#7950E2",
                "type": "color"
            },
            "500": {
                "value": "#592DC8",
                "type": "color"
            },
            "600": {
                "value": "#492A98",
                "type": "color"
            },
            "700": {
                "value": "#38246B",
                "type": "color"
            },
            "800": {
                "value": "#271B46",
                "type": "color"
            },
            "900": {
                "value": "#19132B",
                "type": "color"
            }
        }
    }
}

Palettes built on #100331

Color Lab

Pairs with #100331

UI roles & guardrails

In real applications

Scales

Every model

Export