What color is #3978BF?

#3978BF is a medium blue. In RGB it is rgb(57, 120, 191), and in HSL hsl(212, 54%, 49%).

Is #3978BF accessible as text?

On white, #3978BF has a contrast ratio of 4.55:1 (passes WCAG AA for body text); on black it is 4.61:1 (passes). For text placed on #3978BF, use black for the best readability.

What is the closest Tailwind color to #3978BF?

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

What colors go well with #3978BF?

#3978BF pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #C08139. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #3978BF below.

Is #3978BF good for buttons?

#3978BF works for buttons; black text has the higher contrast, so prefer it for labels.

Is #3978BF the same as CSS steelblue?

No — #3978BF is not the CSS named color steelblue, but steelblue (#4682B4) is the closest CSS named color.

#3978BF Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #3978BF

Not just a swatch — here's how #3978BF works with other colors. Named schemes with #3978BF in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #3978BF Accent #A5C4C1 Surface #DDDBBF Secondary #9AA0A1 Anchor #20344A

Steel 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 #3978BF Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #659DE0

Steel 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 Steel Blue.

Vintage Leather Lead · 5 colors

Lead #3978BF Secondary #7F4537 Surface #E1DDC1 Accent #375246 Anchor #57233B

Steel 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 #3978BF Surface #EDE9D6 Anchor #5A2145 Accent #E4C2CB Secondary #322B2F

Steel 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 #3978BF Secondary #8DA2BC Support #9D8F89 Ink #16140F

Steel 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 Steel Blue carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #3978BF 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 15/100

Cool

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

Softness 44/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 44/100

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 47/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 50/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 35/100

Low

Recognisable but shares space with nearby hues.

UI accent fit 97/100

Very high

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

Surface fit 20/100

Very low

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

Print safety 73/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #3978BF

For UI

For branding

For interior

For fashion

People also use #3978BF with

Medium Turquoise Cerulean Bronze Gainsboro Charcoal

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 4.6:1. Use

Subtle surface Use #DBE4EF for cards and hover fills. Tint 80

Avoid beside #394BC0 — 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 #3978BF 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: #3978BF;
  --color-base-rgb: 57 120 191;
  --color-base-oklch: oklch(56.6% 0.128 253.3);
  --color-50: #F3F7FC;
  --color-100: #DFEAF6;
  --color-200: #C0D5EC;
  --color-300: #95B5DA;
  --color-400: #6C96C6;
  --color-500: #4B77AA;
  --color-600: #3F5F83;
  --color-700: #32465D;
  --color-800: #23303D;
  --color-900: #171E26;
  --color-on-base: #141310;
}

// tailwind.config.js
colors: {
  steel-blue: {
    50: '#F3F7FC',
    100: '#DFEAF6',
    200: '#C0D5EC',
    300: '#95B5DA',
    400: '#6C96C6',
    500: '#4B77AA',
    600: '#3F5F83',
    700: '#32465D',
    800: '#23303D',
    900: '#171E26',
  },
}

$base: #3978BF;
$base-ink: #141310;
$base-50: #F3F7FC;
$base-100: #DFEAF6;
$base-200: #C0D5EC;
$base-300: #95B5DA;
$base-400: #6C96C6;
$base-500: #4B77AA;
$base-600: #3F5F83;
$base-700: #32465D;
$base-800: #23303D;
$base-900: #171E26;
$base-hover: #2E609A;
$base-subtle: #C8D7E8;

{
    "color": {
        "base": {
            "value": "#3978BF",
            "type": "color"
        },
        "onBase": {
            "value": "#141310",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F7FC",
                "type": "color"
            },
            "100": {
                "value": "#DFEAF6",
                "type": "color"
            },
            "200": {
                "value": "#C0D5EC",
                "type": "color"
            },
            "300": {
                "value": "#95B5DA",
                "type": "color"
            },
            "400": {
                "value": "#6C96C6",
                "type": "color"
            },
            "500": {
                "value": "#4B77AA",
                "type": "color"
            },
            "600": {
                "value": "#3F5F83",
                "type": "color"
            },
            "700": {
                "value": "#32465D",
                "type": "color"
            },
            "800": {
                "value": "#23303D",
                "type": "color"
            },
            "900": {
                "value": "#171E26",
                "type": "color"
            }
        }
    }
}

Palettes built on #3978BF

Color Lab

Pairs with #3978BF

UI roles & guardrails

In real applications

Scales

Every model

Export