What color is #43397B?

#43397B is a dark indigo. In RGB it is rgb(67, 57, 123), and in HSL hsl(249, 37%, 35%).

Is #43397B accessible as text?

On white, #43397B has a contrast ratio of 9.95:1 (passes WCAG AA for body text); on black it is 2.11:1 (fails). For text placed on #43397B, use white for the best readability.

What is the closest Tailwind color to #43397B?

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

What colors go well with #43397B?

#43397B pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #707A38. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #43397B below.

Is #43397B good for buttons?

#43397B works well for buttons and highlights, but use white text on #43397B — black text only reaches 2.11:1, below the 4.5:1 needed for normal-size labels.

Is #43397B the same as CSS darkslateblue?

No — #43397B is not the CSS named color darkslateblue, but darkslateblue (#483D8B) is the closest CSS named color.

#43397B Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #43397B

Not just a swatch — here's how #43397B works with other colors. Named schemes with #43397B in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #43397B Accent #A5C4C3 Surface #E9D6BF Secondary #9AA0A1 Anchor #22334A

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

Vintage Leather Lead · 5 colors

Lead #43397B Secondary #7E4633 Surface #EDD8C2 Accent #365247 Anchor #582238

Dark Slate 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.

Modern Café Dominant · 5 colors

Dominant #43397B Anchor #3B2923 Surface #F3E1D2 Accent #759F7C Secondary #3C3734

Dark Slate Blue anchors this café scheme as the warm mid-tone, lifted by latte cream and a muted sage accent and grounded by espresso brown and a warm charcoal.

Berry & Cream Lead · 5 colors

Lead #43397B Surface #F5E5D7 Anchor #5C2141 Accent #E5C2C8 Secondary #332B2F

Dark Slate Blue 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 #43397B Secondary #6A6981 Support #9D9088 Ink #18140F

Dark Slate 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 Dark Slate Blue carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #43397B 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 33/100

Cool

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

Softness 34/100

Low

Middle-weight — neither delicate nor heavy.

Depth 61/100

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 47/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 67/100

High

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

Brand distinctiveness 29/100

Low

Quiet and neutral — a supporting tone, not a signature.

UI accent fit 68/100

High

Strong interactive accent — visible and can carry a legible label.

Surface fit 27/100

Low

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

Print safety 85/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #43397B

For UI

For branding

For interior

For fashion

People also use #43397B with

Lapis Lazuli Eminence 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 10.0:1. Use

Subtle surface Use #D8D5E7 for cards and hover fills. Tint 80

Avoid beside #58387A — 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 #43397B at work across the surfaces designers actually ship.

Website / UI

Northwind Sign up

Build faster.

A working theme, generated in seconds.

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: #43397B;
  --color-base-rgb: 67 57 123;
  --color-base-oklch: oklch(39.0% 0.108 287.3);
  --color-50: #F5F4FA;
  --color-100: #E5E3F3;
  --color-200: #CCC7E5;
  --color-300: #A7A0CF;
  --color-400: #847AB8;
  --color-500: #645A9B;
  --color-600: #514A78;
  --color-700: #3D3856;
  --color-800: #2A2839;
  --color-900: #1B1A24;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  dark-slate-blue: {
    50: '#F5F4FA',
    100: '#E5E3F3',
    200: '#CCC7E5',
    300: '#A7A0CF',
    400: '#847AB8',
    500: '#645A9B',
    600: '#514A78',
    700: '#3D3856',
    800: '#2A2839',
    900: '#1B1A24',
  },
}

$base: #43397B;
$base-ink: #FFFFFF;
$base-50: #F5F4FA;
$base-100: #E5E3F3;
$base-200: #CCC7E5;
$base-300: #A7A0CF;
$base-400: #847AB8;
$base-500: #645A9B;
$base-600: #514A78;
$base-700: #3D3856;
$base-800: #2A2839;
$base-900: #1B1A24;
$base-hover: #352D62;
$base-subtle: #C3BFDB;

{
    "color": {
        "base": {
            "value": "#43397B",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F5F4FA",
                "type": "color"
            },
            "100": {
                "value": "#E5E3F3",
                "type": "color"
            },
            "200": {
                "value": "#CCC7E5",
                "type": "color"
            },
            "300": {
                "value": "#A7A0CF",
                "type": "color"
            },
            "400": {
                "value": "#847AB8",
                "type": "color"
            },
            "500": {
                "value": "#645A9B",
                "type": "color"
            },
            "600": {
                "value": "#514A78",
                "type": "color"
            },
            "700": {
                "value": "#3D3856",
                "type": "color"
            },
            "800": {
                "value": "#2A2839",
                "type": "color"
            },
            "900": {
                "value": "#1B1A24",
                "type": "color"
            }
        }
    }
}

Palettes built on #43397B

Color Lab

Pairs with #43397B

UI roles & guardrails

In real applications

Scales

Every model

Export