What color is #5151CB?

#5151CB is a medium blue-violet. In RGB it is rgb(81, 81, 203), and in HSL hsl(240, 54%, 56%).

Is #5151CB accessible as text?

On white, #5151CB has a contrast ratio of 6.20:1 (passes WCAG AA for body text); on black it is 3.39:1 (fails). For text placed on #5151CB, use white for the best readability.

What is the closest Tailwind color to #5151CB?

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

What colors go well with #5151CB?

#5151CB pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #CBCB52. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #5151CB below.

Is #5151CB good for buttons?

#5151CB works well for buttons and highlights, but use white text on #5151CB — black text only reaches 3.39:1, below the 4.5:1 needed for normal-size labels.

Is #5151CB the same as CSS slateblue?

No — #5151CB is not the CSS named color slateblue, but slateblue (#6A5ACD) is the closest CSS named color.

#5151CB Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #5151CB

Not just a swatch — here's how #5151CB works with other colors. Named schemes with #5151CB in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #5151CB Accent #A5C4C2 Surface #EAD5BF Secondary #9AA0A1 Anchor #22344A

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 #5151CB Secondary #7F4534 Surface #EED7C2 Accent #365247 Anchor #582239

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 #5151CB Anchor #3B2923 Surface #F3E1D2 Accent #769F7B Secondary #3C3734

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 #5151CB Surface #F6E5D8 Anchor #5B2142 Accent #E5C2C9 Secondary #322B2F

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 #5151CB Secondary #848BB6 Support #9D9088 Ink #18140F

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 Slate Blue carrying the quiet middle.

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Color Lab

How #5151CB 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 34/100

Low

Middle-weight — neither delicate nor heavy.

Depth 52/100

Moderate

Mid depth — usable as an accent or a muted ground.

Naturalness 0/100

Very low

Reads engineered rather than organic — synthetic, digital.

Vintage feel 30/100

Low

A faint retro warmth without tipping into sepia.

Luxury 52/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 50/100

Moderate

Recognisable but shares space with nearby hues.

UI accent fit 92/100

Very high

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

Surface fit 8/100

Very low

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

Print safety 71/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #5151CB

For UI

For branding

For interior

For fashion

People also use #5151CB with

Iceberg Amethyst Citrine Gainsboro Prussian Blue

UI roles & guardrails

Primary action Safe as a filled button with white label. AA

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 6.2:1. Use

Subtle surface Use #E0E0F1 for cards and hover fills. Tint 80

Avoid beside #7B52CB — 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 #5151CB 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

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Export

:root {
  --color-base: #5151CB;
  --color-base-rgb: 81 81 203;
  --color-base-oklch: oklch(50.7% 0.184 277.6);
  --color-50: #F3F3FC;
  --color-100: #DFDFF6;
  --color-200: #C0C0EC;
  --color-300: #9595DA;
  --color-400: #6C6CC6;
  --color-500: #4B4BAA;
  --color-600: #3F3F83;
  --color-700: #32325D;
  --color-800: #23233D;
  --color-900: #171726;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  slate-blue: {
    50: '#F3F3FC',
    100: '#DFDFF6',
    200: '#C0C0EC',
    300: '#9595DA',
    400: '#6C6CC6',
    500: '#4B4BAA',
    600: '#3F3F83',
    700: '#32325D',
    800: '#23233D',
    900: '#171726',
  },
}

$base: #5151CB;
$base-ink: #FFFFFF;
$base-50: #F3F3FC;
$base-100: #DFDFF6;
$base-200: #C0C0EC;
$base-300: #9595DA;
$base-400: #6C6CC6;
$base-500: #4B4BAA;
$base-600: #3F3F83;
$base-700: #32325D;
$base-800: #23233D;
$base-900: #171726;
$base-hover: #3535B0;
$base-subtle: #D0D0EB;

{
    "color": {
        "base": {
            "value": "#5151CB",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F3FC",
                "type": "color"
            },
            "100": {
                "value": "#DFDFF6",
                "type": "color"
            },
            "200": {
                "value": "#C0C0EC",
                "type": "color"
            },
            "300": {
                "value": "#9595DA",
                "type": "color"
            },
            "400": {
                "value": "#6C6CC6",
                "type": "color"
            },
            "500": {
                "value": "#4B4BAA",
                "type": "color"
            },
            "600": {
                "value": "#3F3F83",
                "type": "color"
            },
            "700": {
                "value": "#32325D",
                "type": "color"
            },
            "800": {
                "value": "#23233D",
                "type": "color"
            },
            "900": {
                "value": "#171726",
                "type": "color"
            }
        }
    }
}

Palettes built on #5151CB

Color Lab

Pairs with #5151CB

UI roles & guardrails

In real applications

Scales

Every model

Export