What color is #665DEF?

#665DEF is a light, vivid blue-violet. In RGB it is rgb(102, 93, 239), and in HSL hsl(244, 82%, 65%).

Is #665DEF accessible as text?

On white, #665DEF has a contrast ratio of 4.80:1 (passes WCAG AA for body text); on black it is 4.38:1 (fails). For text placed on #665DEF, use white for the best readability.

What is the closest Tailwind color to #665DEF?

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

What colors go well with #665DEF?

#665DEF pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #E5EF5D. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #665DEF below.

Is #665DEF good for buttons?

#665DEF works well for buttons and highlights, but use white text on #665DEF — black text only reaches 4.38:1, below the 4.5:1 needed for normal-size labels.

Is #665DEF the same as CSS mediumslateblue?

No — #665DEF is not the CSS named color mediumslateblue, but mediumslateblue (#7B68EE) is the closest CSS named color.

#665DEF Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #665DEF

Not just a swatch — here's how #665DEF works with other colors. Named schemes with #665DEF in its natural role, and a note on why the supporting colors balance it.

Tech Product Signal · 5 colors

Signal #665DEF Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #8888FF

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 #665DEF Surface #F5E5D8 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 #665DEF Secondary #989DD0 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 #665DEF Accent #A5C4C2 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 #665DEF Secondary #E86A71 Accent #F6934D 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 #665DEF 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 18/100

Cool

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

Softness 34/100

Low

Middle-weight — neither delicate nor heavy.

Depth 46/100

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 22/100

Low

Clean and current — no dusty, aged cast.

Luxury 44/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 82/100

Very high

Bold and ownable — memorable as a primary brand color.

UI accent fit 79/100

High

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

Surface fit 14/100

Very low

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

Print safety 68/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #665DEF

For UI

For branding

For interior

For fashion

People also use #665DEF with

Maya Blue Medium Orchid Pear 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 4.8:1. Use

Subtle surface Use #E4E3F8 for cards and hover fills. Tint 80

Avoid beside #975DEF — 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 #665DEF 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: #665DEF;
  --color-base-rgb: 102 93 239;
  --color-base-oklch: oklch(57.1% 0.212 280.1);
  --color-50: #F1F0FE;
  --color-100: #DBD9FC;
  --color-200: #B9B5F8;
  --color-300: #8A83ED;
  --color-400: #5E55DD;
  --color-500: #3C32C3;
  --color-600: #352E94;
  --color-700: #2B2669;
  --color-800: #1F1D44;
  --color-900: #15142A;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  iris: {
    50: '#F1F0FE',
    100: '#DBD9FC',
    200: '#B9B5F8',
    300: '#8A83ED',
    400: '#5E55DD',
    500: '#3C32C3',
    600: '#352E94',
    700: '#2B2669',
    800: '#1F1D44',
    900: '#15142A',
  },
}

$base: #665DEF;
$base-ink: #FFFFFF;
$base-50: #F1F0FE;
$base-100: #DBD9FC;
$base-200: #B9B5F8;
$base-300: #8A83ED;
$base-400: #5E55DD;
$base-500: #3C32C3;
$base-600: #352E94;
$base-700: #2B2669;
$base-800: #1F1D44;
$base-900: #15142A;
$base-hover: #2E20E9;
$base-subtle: #D6D4F5;

{
    "color": {
        "base": {
            "value": "#665DEF",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F1F0FE",
                "type": "color"
            },
            "100": {
                "value": "#DBD9FC",
                "type": "color"
            },
            "200": {
                "value": "#B9B5F8",
                "type": "color"
            },
            "300": {
                "value": "#8A83ED",
                "type": "color"
            },
            "400": {
                "value": "#5E55DD",
                "type": "color"
            },
            "500": {
                "value": "#3C32C3",
                "type": "color"
            },
            "600": {
                "value": "#352E94",
                "type": "color"
            },
            "700": {
                "value": "#2B2669",
                "type": "color"
            },
            "800": {
                "value": "#1F1D44",
                "type": "color"
            },
            "900": {
                "value": "#15142A",
                "type": "color"
            }
        }
    }
}