What color is #3355EF?

#3355EF is a medium, vivid blue. In RGB it is rgb(51, 85, 239), and in HSL hsl(229, 85%, 57%).

Is #3355EF accessible as text?

On white, #3355EF has a contrast ratio of 5.70:1 (passes WCAG AA for body text); on black it is 3.69:1 (fails). For text placed on #3355EF, use white for the best readability.

What is the closest Tailwind color to #3355EF?

The nearest Tailwind CSS token is blue-600 (#155DFC).

What colors go well with #3355EF?

#3355EF pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #EFCC34. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #3355EF below.

Is #3355EF good for buttons?

#3355EF works well for buttons and highlights, but use white text on #3355EF — black text only reaches 3.69:1, below the 4.5:1 needed for normal-size labels.

Is #3355EF the same as CSS royalblue?

No — #3355EF is not the CSS named color royalblue, but royalblue (#4169E1) is the closest CSS named color.

#3355EF Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #3355EF

Not just a swatch — here's how #3355EF works with other colors. Named schemes with #3355EF in its natural role, and a note on why the supporting colors balance it.

Tech Product Signal · 5 colors

Signal #3355EF Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #5781FF

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

Coastal Morning Lead · 5 colors

Lead #3355EF Accent #A5C4C2 Surface #EAD5C0 Secondary #9AA0A1 Anchor #21344A

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

Berry & Cream Lead · 5 colors

Lead #3355EF Surface #F6E5D8 Anchor #5B2143 Accent #E5C2CA Secondary #322B2F

Neon 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 #3355EF Secondary #7F93C8 Support #9D8F88 Ink #18140F

Neon 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 Neon Blue carrying the quiet middle.

Sunset Warmth Glow · 5 colors

Glow #3355EF Secondary #E86A74 Accent #F79250 Anchor #573B58 Surface #F7E7D7

Neon Blue 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 #3355EF 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 10/100

Cool

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

Softness 30/100

Low

Firm and assertive — carries weight and contrast.

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 14/100

Very low

Clean and current — no dusty, aged cast.

Luxury 47/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 90/100

Very high

Bold and ownable — memorable as a primary brand color.

UI accent fit 71/100

High

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

Surface fit 10/100

Very low

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

Print safety 59/100

Moderate

Prints close, with a slight loss of vibrancy.

Pairs with #3355EF

For UI

For branding

For interior

For fashion

People also use #3355EF with

Bright Sky Blue Violet Saffron Gainsboro Gunmetal Gray

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 5.7:1. Use

Subtle surface Use #DCE1F6 for cards and hover fills. Tint 80

Avoid beside #5034EF — 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 #3355EF 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: #3355EF;
  --color-base-rgb: 51 85 239;
  --color-base-oklch: oklch(52.9% 0.233 267.5);
  --color-50: #F0F3FE;
  --color-100: #D8DFFD;
  --color-200: #B4C0F9;
  --color-300: #8195EE;
  --color-400: #536CDF;
  --color-500: #304BC5;
  --color-600: #2C3F96;
  --color-700: #25326A;
  --color-800: #1C2445;
  --color-900: #13172A;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  neon-blue: {
    50: '#F0F3FE',
    100: '#D8DFFD',
    200: '#B4C0F9',
    300: '#8195EE',
    400: '#536CDF',
    500: '#304BC5',
    600: '#2C3F96',
    700: '#25326A',
    800: '#1C2445',
    900: '#13172A',
  },
}

$base: #3355EF;
$base-ink: #FFFFFF;
$base-50: #F0F3FE;
$base-100: #D8DFFD;
$base-200: #B4C0F9;
$base-300: #8195EE;
$base-400: #536CDF;
$base-500: #304BC5;
$base-600: #2C3F96;
$base-700: #25326A;
$base-800: #1C2445;
$base-900: #13172A;
$base-hover: #1136D7;
$base-subtle: #C9D1F3;

{
    "color": {
        "base": {
            "value": "#3355EF",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F0F3FE",
                "type": "color"
            },
            "100": {
                "value": "#D8DFFD",
                "type": "color"
            },
            "200": {
                "value": "#B4C0F9",
                "type": "color"
            },
            "300": {
                "value": "#8195EE",
                "type": "color"
            },
            "400": {
                "value": "#536CDF",
                "type": "color"
            },
            "500": {
                "value": "#304BC5",
                "type": "color"
            },
            "600": {
                "value": "#2C3F96",
                "type": "color"
            },
            "700": {
                "value": "#25326A",
                "type": "color"
            },
            "800": {
                "value": "#1C2445",
                "type": "color"
            },
            "900": {
                "value": "#13172A",
                "type": "color"
            }
        }
    }
}

Palettes built on #3355EF

Color Lab

Pairs with #3355EF

UI roles & guardrails

In real applications

Scales

Every model

Export