What color is #309FDF?

#309FDF is a medium, vivid cyan-blue. In RGB it is rgb(48, 159, 223), and in HSL hsl(202, 73%, 53%).

Is #309FDF accessible as text?

On white, #309FDF has a contrast ratio of 2.94:1 (fails WCAG AA for body text); on black it is 7.15:1 (passes). For text placed on #309FDF, use black for the best readability.

What is the closest Tailwind color to #309FDF?

The nearest Tailwind CSS token is sky-500 (#00A6F4).

What colors go well with #309FDF?

#309FDF pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #DF7030. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #309FDF below.

Is #309FDF good for buttons?

#309FDF works well for buttons and highlights, but use black text on #309FDF — white text only reaches 2.94:1, below the 4.5:1 needed for normal-size labels.

Is #309FDF the same as CSS cornflowerblue?

No — #309FDF is not the CSS named color cornflowerblue, but cornflowerblue (#6495ED) is the closest CSS named color.

#309FDF Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #309FDF

Not just a swatch — here's how #309FDF works with other colors. Named schemes with #309FDF in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #309FDF Accent #A5C4C0 Surface #DEDABF Secondary #9AA0A0 Anchor #1F344A

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

Nordic Calm Accent · 5 colors

Accent #309FDF Secondary #AEB4B8 Surface #F1F2F0 Support #7C93A6 Anchor #2E3236

Carolina Blue keeps this Nordic scheme quiet — cool greys and a soft white around it, a muted-blue support and a charcoal anchor.

Tech Product Signal · 5 colors

Signal #309FDF Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #6AC5FF

Carolina 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 Carolina Blue.

Minimal Editorial Surface · 5 colors

Surface #F6F4EF Accent #309FDF Secondary #A6C6DD Support #969386 Ink #16140F

Carolina 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 Carolina Blue carrying the quiet middle.

Modern Café Dominant · 5 colors

Dominant #309FDF Anchor #3C2925 Surface #EAE5D0 Accent #7B9E77 Secondary #393933

Carolina Blue 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.

Build a working theme in the generator →

Color Lab

How #309FDF 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 51/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 34/100

Low

Mid depth — usable as an accent or a muted ground.

Naturalness 0/100

Very low

Reads engineered rather than organic — synthetic, digital.

Vintage feel 37/100

Low

A faint retro warmth without tipping into sepia.

Luxury 40/100

Low

Understated — leans refined without going austere.

Brand distinctiveness 52/100

Moderate

Recognisable but shares space with nearby hues.

UI accent fit 71/100

High

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

Surface fit 28/100

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 #309FDF

For UI

For branding

For interior

For fashion

People also use #309FDF with

Turquoise Ultramarine Chocolate Platinum 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 Only on dark surfaces. Avoid

Background Pair with #141310 text at 6.3:1. Use

Subtle surface Use #DAEAF4 for cards and hover fills. Tint 80

Avoid beside #3064DF — 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 #309FDF 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: #309FDF;
  --color-base-rgb: 48 159 223;
  --color-base-oklch: oklch(67.0% 0.135 239.4);
  --color-50: #F1F9FD;
  --color-100: #DBEFFA;
  --color-200: #B9DEF4;
  --color-300: #88C4E7;
  --color-400: #5DA9D5;
  --color-500: #3A8CBB;
  --color-600: #336D8E;
  --color-700: #2A4F65;
  --color-800: #1F3542;
  --color-900: #152128;
  --color-on-base: #141310;
}

// tailwind.config.js
colors: {
  carolina-blue: {
    50: '#F1F9FD',
    100: '#DBEFFA',
    200: '#B9DEF4',
    300: '#88C4E7',
    400: '#5DA9D5',
    500: '#3A8CBB',
    600: '#336D8E',
    700: '#2A4F65',
    800: '#1F3542',
    900: '#152128',
  },
}

$base: #309FDF;
$base-ink: #141310;
$base-50: #F1F9FD;
$base-100: #DBEFFA;
$base-200: #B9DEF4;
$base-300: #88C4E7;
$base-400: #5DA9D5;
$base-500: #3A8CBB;
$base-600: #336D8E;
$base-700: #2A4F65;
$base-800: #1F3542;
$base-900: #152128;
$base-hover: #1D81BB;
$base-subtle: #C7E0EF;

{
    "color": {
        "base": {
            "value": "#309FDF",
            "type": "color"
        },
        "onBase": {
            "value": "#141310",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F1F9FD",
                "type": "color"
            },
            "100": {
                "value": "#DBEFFA",
                "type": "color"
            },
            "200": {
                "value": "#B9DEF4",
                "type": "color"
            },
            "300": {
                "value": "#88C4E7",
                "type": "color"
            },
            "400": {
                "value": "#5DA9D5",
                "type": "color"
            },
            "500": {
                "value": "#3A8CBB",
                "type": "color"
            },
            "600": {
                "value": "#336D8E",
                "type": "color"
            },
            "700": {
                "value": "#2A4F65",
                "type": "color"
            },
            "800": {
                "value": "#1F3542",
                "type": "color"
            },
            "900": {
                "value": "#152128",
                "type": "color"
            }
        }
    }
}