What color is #3F9DFB?

#3F9DFB is a light, vivid blue. In RGB it is rgb(63, 157, 251), and in HSL hsl(210, 96%, 62%).

Is #3F9DFB accessible as text?

On white, #3F9DFB has a contrast ratio of 2.83:1 (fails WCAG AA for body text); on black it is 7.43:1 (passes). For text placed on #3F9DFB, use black for the best readability.

What is the closest Tailwind color to #3F9DFB?

The nearest Tailwind CSS token is blue-400 (#51A2FF).

What colors go well with #3F9DFB?

#3F9DFB pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #FB9E41. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #3F9DFB below.

Is #3F9DFB good for buttons?

#3F9DFB works well for buttons and highlights, but use black text on #3F9DFB — white text only reaches 2.83:1, below the 4.5:1 needed for normal-size labels.

Is #3F9DFB the same as CSS cornflowerblue?

No — #3F9DFB is not the CSS named color cornflowerblue, but cornflowerblue (#6495ED) is the closest CSS named color.

#3F9DFB Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #3F9DFB

Not just a swatch — here's how #3F9DFB works with other colors. Named schemes with #3F9DFB in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #3F9DFB Accent #A5C4C1 Surface #DDDBBF Secondary #9AA0A1 Anchor #20344A

Cornflower 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 #3F9DFB Secondary #AEB4B8 Surface #F1F2F0 Support #7C93A6 Anchor #2E3236

Cornflower 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 #3F9DFB Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #73C4FF

Cornflower 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 Cornflower Blue.

Minimal Editorial Surface · 5 colors

Surface #F6F4EF Accent #3F9DFB Secondary #ABC9EB Support #959386 Ink #16140F

Cornflower 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 Cornflower Blue carrying the quiet middle.

Modern Café Dominant · 5 colors

Dominant #3F9DFB Anchor #3B2924 Surface #EAE5D0 Accent #799E78 Secondary #393933

Cornflower 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 #3F9DFB 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 5/100

Cool

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

Softness 47/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 33/100

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 29/100

Low

A faint retro warmth without tipping into sepia.

Luxury 37/100

Low

Understated — leans refined without going austere.

Brand distinctiveness 63/100

High

Bold and ownable — memorable as a primary brand color.

UI accent fit 65/100

High

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

Surface fit 25/100

Low

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

Print safety 65/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #3F9DFB

For UI

For branding

For interior

For fashion

People also use #3F9DFB with

Electric Blue Han Purple Buff 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 Only on dark surfaces. Avoid

Background Pair with #141310 text at 6.6:1. Use

Subtle surface Use #DEECF9 for cards and hover fills. Tint 80

Avoid beside #4160FB — 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 #3F9DFB 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: #3F9DFB;
  --color-base-rgb: 63 157 251;
  --color-base-oklch: oklch(68.5% 0.164 251.5);
  --color-50: #F0F7FE;
  --color-100: #D8EBFD;
  --color-200: #B1D6FC;
  --color-300: #7AB8F6;
  --color-400: #4A99E8;
  --color-500: #267ACF;
  --color-600: #25619D;
  --color-700: #21476E;
  --color-800: #193048;
  --color-900: #121F2C;
  --color-on-base: #141310;
}

// tailwind.config.js
colors: {
  cornflower-blue: {
    50: '#F0F7FE',
    100: '#D8EBFD',
    200: '#B1D6FC',
    300: '#7AB8F6',
    400: '#4A99E8',
    500: '#267ACF',
    600: '#25619D',
    700: '#21476E',
    800: '#193048',
    900: '#121F2C',
  },
}

$base: #3F9DFB;
$base-ink: #141310;
$base-50: #F0F7FE;
$base-100: #D8EBFD;
$base-200: #B1D6FC;
$base-300: #7AB8F6;
$base-400: #4A99E8;
$base-500: #267ACF;
$base-600: #25619D;
$base-700: #21476E;
$base-800: #193048;
$base-900: #121F2C;
$base-hover: #057EF8;
$base-subtle: #CDE2F7;

{
    "color": {
        "base": {
            "value": "#3F9DFB",
            "type": "color"
        },
        "onBase": {
            "value": "#141310",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F0F7FE",
                "type": "color"
            },
            "100": {
                "value": "#D8EBFD",
                "type": "color"
            },
            "200": {
                "value": "#B1D6FC",
                "type": "color"
            },
            "300": {
                "value": "#7AB8F6",
                "type": "color"
            },
            "400": {
                "value": "#4A99E8",
                "type": "color"
            },
            "500": {
                "value": "#267ACF",
                "type": "color"
            },
            "600": {
                "value": "#25619D",
                "type": "color"
            },
            "700": {
                "value": "#21476E",
                "type": "color"
            },
            "800": {
                "value": "#193048",
                "type": "color"
            },
            "900": {
                "value": "#121F2C",
                "type": "color"
            }
        }
    }
}

Palettes built on #3F9DFB

Color Lab

Pairs with #3F9DFB

UI roles & guardrails

In real applications

Scales

Every model

Export