What color is #3D3366?

#3D3366 is a dark, muted indigo. In RGB it is rgb(61, 51, 102), and in HSL hsl(252, 33%, 30%).

Is #3D3366 accessible as text?

On white, #3D3366 has a contrast ratio of 11.27:1 (passes WCAG AA for body text); on black it is 1.86:1 (fails). For text placed on #3D3366, use white for the best readability.

What is the closest Tailwind color to #3D3366?

The nearest Tailwind CSS token is indigo-900 (#312C85).

What colors go well with #3D3366?

#3D3366 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #5C6633. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #3D3366 below.

Is #3D3366 good for buttons?

#3D3366 works well for buttons and highlights, but use white text on #3D3366 — black text only reaches 1.86:1, below the 4.5:1 needed for normal-size labels.

Is #3D3366 the same as CSS darkslateblue?

No — #3D3366 is not the CSS named color darkslateblue, but darkslateblue (#483D8B) is the closest CSS named color.

#3D3366 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #3D3366

Not just a swatch — here's how #3D3366 works with other colors. Named schemes with #3D3366 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #3D3366 Accent #A5C4C3 Surface #E9D6BF Secondary #9AA0A1 Anchor #22334A

Yale Blue 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 #3D3366 Secondary #AFB4B8 Surface #F1F2F0 Support #7F92A7 Anchor #2E3236

Yale Blue 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 #3D3366 Secondary #7E4633 Surface #EDD8C2 Accent #355248 Anchor #582237

Yale 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.

Luxury Packaging Feature · 5 colors

Feature #3D3366 Anchor #141210 Accent #DB9757 Secondary #292732 Surface #F3ECE3

Yale 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.

Minimal Editorial Surface · 5 colors

Surface #F8F4EF Accent #3D3366 Secondary #626073 Support #9D9088 Ink #18140F

Yale 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 Yale Blue carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #3D3366 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 37/100

Cool

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

Softness 33/100

Low

Middle-weight — neither delicate nor heavy.

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 49/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 68/100

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 53/100

Moderate

Workable accent with care around contrast.

Surface fit 36/100

Low

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 #3D3366

For UI

For branding

For interior

For fashion

People also use #3D3366 with

Lapis Lazuli Byzantium Dark Olive Green 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 11.3:1. Use

Subtle surface Use #D6D3E4 for cards and hover fills. Tint 80

Avoid beside #4E3366 — 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 #3D3366 at work across the surfaces designers actually ship.

Website / UI

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Build faster.

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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: #3D3366;
  --color-base-rgb: 61 51 102;
  --color-base-oklch: oklch(35.8% 0.086 290.4);
  --color-50: #F6F5FA;
  --color-100: #E6E3F2;
  --color-200: #CEC9E4;
  --color-300: #ABA2CD;
  --color-400: #897EB4;
  --color-500: #695D97;
  --color-600: #554C75;
  --color-700: #3F3A55;
  --color-800: #2C2938;
  --color-900: #1C1A23;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  yale-blue: {
    50: '#F6F5FA',
    100: '#E6E3F2',
    200: '#CEC9E4',
    300: '#ABA2CD',
    400: '#897EB4',
    500: '#695D97',
    600: '#554C75',
    700: '#3F3A55',
    800: '#2C2938',
    900: '#1C1A23',
  },
}

$base: #3D3366;
$base-ink: #FFFFFF;
$base-50: #F6F5FA;
$base-100: #E6E3F2;
$base-200: #CEC9E4;
$base-300: #ABA2CD;
$base-400: #897EB4;
$base-500: #695D97;
$base-600: #554C75;
$base-700: #3F3A55;
$base-800: #2C2938;
$base-900: #1C1A23;
$base-hover: #312951;
$base-subtle: #C1BCD7;

{
    "color": {
        "base": {
            "value": "#3D3366",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F6F5FA",
                "type": "color"
            },
            "100": {
                "value": "#E6E3F2",
                "type": "color"
            },
            "200": {
                "value": "#CEC9E4",
                "type": "color"
            },
            "300": {
                "value": "#ABA2CD",
                "type": "color"
            },
            "400": {
                "value": "#897EB4",
                "type": "color"
            },
            "500": {
                "value": "#695D97",
                "type": "color"
            },
            "600": {
                "value": "#554C75",
                "type": "color"
            },
            "700": {
                "value": "#3F3A55",
                "type": "color"
            },
            "800": {
                "value": "#2C2938",
                "type": "color"
            },
            "900": {
                "value": "#1C1A23",
                "type": "color"
            }
        }
    }
}