What color is #643FE9?

#643FE9 is a medium, vivid indigo. In RGB it is rgb(100, 63, 233), and in HSL hsl(253, 79%, 58%).

Is #643FE9 accessible as text?

On white, #643FE9 has a contrast ratio of 6.12:1 (passes WCAG AA for body text); on black it is 3.43:1 (fails). For text placed on #643FE9, use white for the best readability.

What is the closest Tailwind color to #643FE9?

The nearest Tailwind CSS token is indigo-600 (#4F39F6).

What colors go well with #643FE9?

#643FE9 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #C4E93F. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #643FE9 below.

Is #643FE9 good for buttons?

#643FE9 works well for buttons and highlights, but use white text on #643FE9 — black text only reaches 3.43:1, below the 4.5:1 needed for normal-size labels.

Is #643FE9 the same as CSS slateblue?

No — #643FE9 is not the CSS named color slateblue, but slateblue (#6A5ACD) is the closest CSS named color.

#643FE9 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #643FE9

Not just a swatch — here's how #643FE9 works with other colors. Named schemes with #643FE9 in its natural role, and a note on why the supporting colors balance it.

Tech Product Signal · 5 colors

Signal #643FE9 Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #8370FF

Iris is the vivid signal in this product UI — on a near-black surface with cool white, a slate grey and a lighter tint of Iris.

Berry & Cream Lead · 5 colors

Lead #643FE9 Surface #F5E5D7 Anchor #5B2142 Accent #E5C2C8 Secondary #332B2F

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 #643FE9 Secondary #8C8CC4 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.

Coastal Morning Lead · 5 colors

Lead #643FE9 Accent #A5C4C3 Surface #EAD5BF Secondary #9AA0A1 Anchor #22334A

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

Sunset Warmth Glow · 5 colors

Glow #643FE9 Secondary #E86A6F Accent #F5934C Anchor #583B57 Surface #F7E7D7

Iris glows at the center of this sunset palette, joined by coral and gold, deepened by a plum anchor and cooled with cream.

Build a working theme in the generator →

Color Lab

How #643FE9 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 21/100

Cool

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

Softness 29/100

Low

Firm and assertive — carries weight and contrast.

Depth 53/100

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 13/100

Very low

Clean and current — no dusty, aged cast.

Luxury 47/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 92/100

Very high

Bold and ownable — memorable as a primary brand color.

UI accent fit 68/100

High

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

Surface fit 9/100

Very low

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

Print safety 66/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #643FE9

For UI

For branding

For interior

For fashion

People also use #643FE9 with

Cornflower Blue Medium Orchid Pear Gainsboro Russian Violet

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 6.1:1. Use

Subtle surface Use #E3DDF6 for cards and hover fills. Tint 80

Avoid beside #9C3FE9 — 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 #643FE9 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: #643FE9;
  --color-base-rgb: 100 63 233;
  --color-base-oklch: oklch(52.1% 0.238 284.5);
  --color-50: #F4F1FE;
  --color-100: #E1DAFC;
  --color-200: #C4B6F6;
  --color-300: #9B85EB;
  --color-400: #7458DA;
  --color-500: #5335C0;
  --color-600: #453092;
  --color-700: #352867;
  --color-800: #261D43;
  --color-900: #191429;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  iris: {
    50: '#F4F1FE',
    100: '#E1DAFC',
    200: '#C4B6F6',
    300: '#9B85EB',
    400: '#7458DA',
    500: '#5335C0',
    600: '#453092',
    700: '#352867',
    800: '#261D43',
    900: '#191429',
  },
}

$base: #643FE9;
$base-ink: #FFFFFF;
$base-50: #F4F1FE;
$base-100: #E1DAFC;
$base-200: #C4B6F6;
$base-300: #9B85EB;
$base-400: #7458DA;
$base-500: #5335C0;
$base-600: #453092;
$base-700: #352867;
$base-800: #261D43;
$base-900: #191429;
$base-hover: #4119D4;
$base-subtle: #D4CCF2;

{
    "color": {
        "base": {
            "value": "#643FE9",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F4F1FE",
                "type": "color"
            },
            "100": {
                "value": "#E1DAFC",
                "type": "color"
            },
            "200": {
                "value": "#C4B6F6",
                "type": "color"
            },
            "300": {
                "value": "#9B85EB",
                "type": "color"
            },
            "400": {
                "value": "#7458DA",
                "type": "color"
            },
            "500": {
                "value": "#5335C0",
                "type": "color"
            },
            "600": {
                "value": "#453092",
                "type": "color"
            },
            "700": {
                "value": "#352867",
                "type": "color"
            },
            "800": {
                "value": "#261D43",
                "type": "color"
            },
            "900": {
                "value": "#191429",
                "type": "color"
            }
        }
    }
}

Palettes built on #643FE9

Color Lab

Pairs with #643FE9

UI roles & guardrails

In real applications

Scales

Every model

Export