What color is #337DDE?

#337DDE is a medium, vivid blue. In RGB it is rgb(51, 125, 222), and in HSL hsl(214, 72%, 54%).

Is #337DDE accessible as text?

On white, #337DDE has a contrast ratio of 4.09:1 (fails WCAG AA for body text); on black it is 5.13:1 (passes). For text placed on #337DDE, use black for the best readability.

What is the closest Tailwind color to #337DDE?

The nearest Tailwind CSS token is sky-600 (#0084D1).

What colors go well with #337DDE?

#337DDE pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #DE9535. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #337DDE below.

Is #337DDE good for buttons?

#337DDE works well for buttons and highlights, but use black text on #337DDE — white text only reaches 4.09:1, below the 4.5:1 needed for normal-size labels.

Is #337DDE the same as CSS royalblue?

No — #337DDE is not the CSS named color royalblue, but royalblue (#4169E1) is the closest CSS named color.

#337DDE Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #337DDE

Not just a swatch — here's how #337DDE works with other colors. Named schemes with #337DDE in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #337DDE Accent #A5C4C1 Surface #DDDBBF Secondary #9AA0A1 Anchor #20344A

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

Tech Product Signal · 5 colors

Signal #337DDE Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #62A4FE

True 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 True Blue.

Vintage Leather Lead · 5 colors

Lead #337DDE Secondary #7F4537 Surface #E1DDC1 Accent #375246 Anchor #57233B

True 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.

Berry & Cream Lead · 5 colors

Lead #337DDE Surface #EDE9D6 Anchor #5A2145 Accent #E4C2CA Secondary #322B2F

True Blue sits between cream and a deep berry here, softened by a blush accent and grounded by charcoal.

Minimal Editorial Surface · 5 colors

Surface #F6F4EF Accent #337DDE Secondary #92ABCE Support #9D8F89 Ink #16140F

True 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 True Blue carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #337DDE 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 6/100

Cool

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

Softness 42/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 42/100

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 34/100

Low

A faint retro warmth without tipping into sepia.

Luxury 45/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 45/100

Moderate

Recognisable but shares space with nearby hues.

UI accent fit 91/100

Very high

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

Surface fit 16/100

Very low

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

Print safety 67/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #337DDE

For UI

For branding

For interior

For fashion

People also use #337DDE with

Turquoise Han Purple Butterscotch Gainsboro Charcoal

UI roles & guardrails

Primary action Safe as a filled button with near-black label. AA

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

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

Background Pair with #141310 text at 4.5:1. Use

Subtle surface Use #DBE6F4 for cards and hover fills. Tint 80

Avoid beside #3546DE — 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 #337DDE 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: #337DDE;
  --color-base-rgb: 51 125 222;
  --color-base-oklch: oklch(59.4% 0.165 256.6);
  --color-50: #F1F7FD;
  --color-100: #DBE9FA;
  --color-200: #B9D2F3;
  --color-300: #89B1E6;
  --color-400: #5D91D5;
  --color-500: #3B72BA;
  --color-600: #345B8E;
  --color-700: #2A4464;
  --color-800: #1F2E42;
  --color-900: #151D28;
  --color-on-base: #141310;
}

// tailwind.config.js
colors: {
  true-blue: {
    50: '#F1F7FD',
    100: '#DBE9FA',
    200: '#B9D2F3',
    300: '#89B1E6',
    400: '#5D91D5',
    500: '#3B72BA',
    600: '#345B8E',
    700: '#2A4464',
    800: '#1F2E42',
    900: '#151D28',
  },
}

$base: #337DDE;
$base-ink: #141310;
$base-50: #F1F7FD;
$base-100: #DBE9FA;
$base-200: #B9D2F3;
$base-300: #89B1E6;
$base-400: #5D91D5;
$base-500: #3B72BA;
$base-600: #345B8E;
$base-700: #2A4464;
$base-800: #1F2E42;
$base-900: #151D28;
$base-hover: #1F64BD;
$base-subtle: #C9D9EF;

{
    "color": {
        "base": {
            "value": "#337DDE",
            "type": "color"
        },
        "onBase": {
            "value": "#141310",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F1F7FD",
                "type": "color"
            },
            "100": {
                "value": "#DBE9FA",
                "type": "color"
            },
            "200": {
                "value": "#B9D2F3",
                "type": "color"
            },
            "300": {
                "value": "#89B1E6",
                "type": "color"
            },
            "400": {
                "value": "#5D91D5",
                "type": "color"
            },
            "500": {
                "value": "#3B72BA",
                "type": "color"
            },
            "600": {
                "value": "#345B8E",
                "type": "color"
            },
            "700": {
                "value": "#2A4464",
                "type": "color"
            },
            "800": {
                "value": "#1F2E42",
                "type": "color"
            },
            "900": {
                "value": "#151D28",
                "type": "color"
            }
        }
    }
}

Palettes built on #337DDE

Color Lab

Pairs with #337DDE

UI roles & guardrails

In real applications

Scales

Every model

Export