What color is #647C8A?

#647C8A is a medium low-chroma blue-gray with a subtle blue cast. In RGB it is rgb(100, 124, 138), and in HSL hsl(202, 16%, 47%).

Is #647C8A accessible as text?

On white, #647C8A has a contrast ratio of 4.38:1 (fails WCAG AA for body text); on black it is 4.79:1 (passes). For text placed on #647C8A, use black for the best readability.

What is the closest Tailwind color to #647C8A?

The nearest Tailwind CSS token is slate-500 (#62748E).

What colors go well with #647C8A?

As a neutral, #647C8A pairs cleanly with either light or dark text depending on the surface, and sits under accent hues like blue, violet, emerald or warm orange — use it as a muted neutral, divider, icon or disabled-state color and let the accent carry the color.

Is #647C8A the same as CSS slategray?

No — #647C8A is not the CSS named color slategray, but slategray (#708090) is the closest CSS named color.

#647C8A Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #647C8A

Not just a swatch — here's how #647C8A works with other colors. Named schemes with #647C8A in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #647C8A Accent #A6C4C0 Surface #DEDABF Secondary #9AA0A0 Anchor #1F344A

Slate Gray 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 #647C8A Secondary #AEB4B8 Surface #F1F2F0 Support #7C93A6 Anchor #2E3236

Slate Gray 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 #647C8A Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #89A0AD

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

Vintage Leather Lead · 5 colors

Lead #647C8A Secondary #6F5216 Surface #E2DCC0 Accent #385244 Anchor #57233D

Slate Gray plays the worn-leather lead, deepened by saddle brown and an oxblood anchor, softened by aged cream and cooled by a muted forest green.

Minimal Editorial Surface · 5 colors

Surface #F6F4EF Accent #647C8A Secondary #9BA4A9 Support #969386 Ink #16140F

Slate Gray 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 Slate Gray carrying the quiet middle.

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Color Lab

How #647C8A 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 40/100

Neutral

Balanced temperature — flexible, sits between warm and cool schemes.

Softness 56/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 40/100

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 41/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 46/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 14/100

Very low

Quiet and neutral — a supporting tone, not a signature.

UI accent fit 62/100

High

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

Surface fit 49/100

Moderate

Usable as a tinted surface in measured doses.

Print safety 91/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #647C8A

For UI

For branding

For interior

For fashion

People also use #647C8A with

Cadet Blue Very Peri Shadow Platinum Charcoal

UI roles & guardrails

Primary action Too mid-tone for a filled button — darken for the fill. AA Large

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

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

Background Pair with white text at 4.4:1. Use

Subtle surface Use #E1E5E7 for cards and hover fills. Tint 80

Avoid beside #65708B — 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 #647C8A 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: #647C8A;
  --color-base-rgb: 100 124 138;
  --color-base-oklch: oklch(57.2% 0.035 233.8);
  --color-50: #F6F8F9;
  --color-100: #E7ECEE;
  --color-200: #D0D8DD;
  --color-300: #ADBAC2;
  --color-400: #8C9DA6;
  --color-500: #6C7E88;
  --color-600: #57646B;
  --color-700: #41494E;
  --color-800: #2D3134;
  --color-900: #1C1F21;
  --color-on-base: #141310;
}

// tailwind.config.js
colors: {
  slate-gray: {
    50: '#F6F8F9',
    100: '#E7ECEE',
    200: '#D0D8DD',
    300: '#ADBAC2',
    400: '#8C9DA6',
    500: '#6C7E88',
    600: '#57646B',
    700: '#41494E',
    800: '#2D3134',
    900: '#1C1F21',
  },
}

$base: #647C8A;
$base-ink: #141310;
$base-50: #F6F8F9;
$base-100: #E7ECEE;
$base-200: #D0D8DD;
$base-300: #ADBAC2;
$base-400: #8C9DA6;
$base-500: #6C7E88;
$base-600: #57646B;
$base-700: #41494E;
$base-800: #2D3134;
$base-900: #1C1F21;
$base-hover: #51646F;
$base-subtle: #D2D8DB;

{
    "color": {
        "base": {
            "value": "#647C8A",
            "type": "color"
        },
        "onBase": {
            "value": "#141310",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F6F8F9",
                "type": "color"
            },
            "100": {
                "value": "#E7ECEE",
                "type": "color"
            },
            "200": {
                "value": "#D0D8DD",
                "type": "color"
            },
            "300": {
                "value": "#ADBAC2",
                "type": "color"
            },
            "400": {
                "value": "#8C9DA6",
                "type": "color"
            },
            "500": {
                "value": "#6C7E88",
                "type": "color"
            },
            "600": {
                "value": "#57646B",
                "type": "color"
            },
            "700": {
                "value": "#41494E",
                "type": "color"
            },
            "800": {
                "value": "#2D3134",
                "type": "color"
            },
            "900": {
                "value": "#1C1F21",
                "type": "color"
            }
        }
    }
}

Palettes built on #647C8A

Color Lab

Pairs with #647C8A

UI roles & guardrails

In real applications

Scales

Every model

Export