What color is #646CDD?

#646CDD is a light, soft blue-violet. In RGB it is rgb(100, 108, 221), and in HSL hsl(236, 64%, 63%).

Is #646CDD accessible as text?

On white, #646CDD has a contrast ratio of 4.44:1 (fails WCAG AA for body text); on black it is 4.73:1 (passes). For text placed on #646CDD, use black for the best readability.

What is the closest Tailwind color to #646CDD?

The nearest Tailwind CSS token is indigo-500 (#615FFF).

What colors go well with #646CDD?

#646CDD pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #DDD564. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #646CDD below.

Is #646CDD good for buttons?

#646CDD works well for buttons and highlights, but use black text on #646CDD — white text only reaches 4.44:1, below the 4.5:1 needed for normal-size labels.

Is #646CDD the same as CSS mediumslateblue?

No — #646CDD is not the CSS named color mediumslateblue, but mediumslateblue (#7B68EE) is the closest CSS named color.

#646CDD Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #646CDD

Not just a swatch — here's how #646CDD works with other colors. Named schemes with #646CDD in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #646CDD Accent #A5C4C2 Surface #EAD5BF Secondary #9AA0A1 Anchor #22344A

Iris 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 #646CDD Secondary #7F4534 Surface #EED7C2 Accent #365247 Anchor #582239

Iris 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 #646CDD Anchor #3B2923 Surface #F3E1D2 Accent #769F7B Secondary #3C3734

Iris 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 #646CDD Surface #F6E5D8 Anchor #5B2142 Accent #E5C2C9 Secondary #322B2F

Iris 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 #646CDD Secondary #9BA3CB Support #9D9088 Ink #18140F

Iris 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 Iris carrying the quiet middle.

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Color Lab

How #646CDD 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 40/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 44/100

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 35/100

Low

A faint retro warmth without tipping into sepia.

Luxury 46/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 46/100

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 15/100

Very low

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

Print safety 73/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #646CDD

For UI

For branding

For interior

For fashion

People also use #646CDD with

Sky Blue Amethyst Flax Gainsboro Prussian Blue

UI roles & guardrails

Primary action Too mid-tone for a filled button — darken for the fill. AA Large

Body text Do not use for body copy on light surfaces. Avoid

Large display Fine for headings 24px+ on white. Pass

Background Pair with white text at 4.4:1. Use

Subtle surface Use #E3E5F5 for cards and hover fills. Tint 80

Avoid beside #8464DD — 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 #646CDD 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: #646CDD;
  --color-base-rgb: 100 108 221;
  --color-base-oklch: oklch(58.3% 0.170 276.7);
  --color-50: #F2F3FD;
  --color-100: #DDDFF8;
  --color-200: #BCC0F0;
  --color-300: #8E94E1;
  --color-400: #646BCE;
  --color-500: #424AB3;
  --color-600: #393E89;
  --color-700: #2E3161;
  --color-800: #212340;
  --color-900: #161727;
  --color-on-base: #141310;
}

// tailwind.config.js
colors: {
  iris: {
    50: '#F2F3FD',
    100: '#DDDFF8',
    200: '#BCC0F0',
    300: '#8E94E1',
    400: '#646BCE',
    500: '#424AB3',
    600: '#393E89',
    700: '#2E3161',
    800: '#212340',
    900: '#161727',
  },
}

$base: #646CDD;
$base-ink: #141310;
$base-50: #F2F3FD;
$base-100: #DDDFF8;
$base-200: #BCC0F0;
$base-300: #8E94E1;
$base-400: #646BCE;
$base-500: #424AB3;
$base-600: #393E89;
$base-700: #2E3161;
$base-800: #212340;
$base-900: #161727;
$base-hover: #303AD1;
$base-subtle: #D5D7F0;

{
    "color": {
        "base": {
            "value": "#646CDD",
            "type": "color"
        },
        "onBase": {
            "value": "#141310",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F2F3FD",
                "type": "color"
            },
            "100": {
                "value": "#DDDFF8",
                "type": "color"
            },
            "200": {
                "value": "#BCC0F0",
                "type": "color"
            },
            "300": {
                "value": "#8E94E1",
                "type": "color"
            },
            "400": {
                "value": "#646BCE",
                "type": "color"
            },
            "500": {
                "value": "#424AB3",
                "type": "color"
            },
            "600": {
                "value": "#393E89",
                "type": "color"
            },
            "700": {
                "value": "#2E3161",
                "type": "color"
            },
            "800": {
                "value": "#212340",
                "type": "color"
            },
            "900": {
                "value": "#161727",
                "type": "color"
            }
        }
    }
}

Palettes built on #646CDD

Color Lab

Pairs with #646CDD

UI roles & guardrails

In real applications

Scales

Every model

Export