What color is #2100A5?

#2100A5 is a dark, vivid indigo. In RGB it is rgb(33, 0, 165), and in HSL hsl(252, 100%, 32%).

Is #2100A5 accessible as text?

On white, #2100A5 has a contrast ratio of 13.06:1 (passes WCAG AA for body text); on black it is 1.61:1 (fails). For text placed on #2100A5, use white for the best readability.

What is the closest Tailwind color to #2100A5?

The nearest Tailwind CSS token is indigo-800 (#372AAC).

What colors go well with #2100A5?

#2100A5 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #83A300. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #2100A5 below.

Is #2100A5 good for buttons?

#2100A5 works well for buttons and highlights, but use white text on #2100A5 — black text only reaches 1.61:1, below the 4.5:1 needed for normal-size labels.

Is #2100A5 the same as CSS darkblue?

No — #2100A5 is not the CSS named color darkblue, but darkblue (#00008B) is the closest CSS named color.

#2100A5 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #2100A5

Not just a swatch — here's how #2100A5 works with other colors. Named schemes with #2100A5 in its natural role, and a note on why the supporting colors balance it.

Luxury Packaging Feature · 5 colors

Feature #2100A5 Anchor #141210 Accent #DC9659 Secondary #252833 Surface #F3ECE3

Zaffre carries the depth in this luxury scheme, offset by a brass accent and near-black and held together by a deep neutral and an off-white surface.

Tech Product Signal · 5 colors

Signal #2100A5 Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #3743C2

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

Moody Editorial Color · 5 colors

Color #2100A5 Anchor #2A2A2E Secondary #6E6E74 Surface #EEE5DB Accent #21005A

Zaffre adds the colour to this moody editorial scheme — charcoal and a mid-grey around it, a bone highlight, and a muted jewel accent drawn from Zaffre.

Coastal Morning Lead · 5 colors

Lead #2100A5 Accent #A5C4C2 Surface #EAD5C0 Secondary #9AA0A1 Anchor #21344A

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

Minimal Editorial Surface · 5 colors

Surface #F8F4EF Accent #2100A5 Secondary #4E5A89 Support #9D8F88 Ink #18140F

Zaffre 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 Zaffre carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #2100A5 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 13/100

Cool

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

Softness 21/100

Low

Firm and assertive — carries weight and contrast.

Depth 72/100

High

Deep and grounding — anchors a layout, strong dark-mode base.

Naturalness 0/100

Very low

Reads engineered rather than organic — synthetic, digital.

Vintage feel 13/100

Very low

Clean and current — no dusty, aged cast.

Luxury 62/100

High

Restrained and premium — deep, quiet, high-end packaging and fashion.

Brand distinctiveness 84/100

Very high

Bold and ownable — memorable as a primary brand color.

UI accent fit 42/100

Moderate

Workable accent with care around contrast.

Surface fit 18/100

Very low

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

Print safety 64/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #2100A5

For UI

For branding

For interior

For fashion

People also use #2100A5 with

Sapphire Blue Mauveine Olive Drab Gainsboro Prussian Blue

UI roles & guardrails

Primary action Safe as a filled button with white label. AAA

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 13.1:1. Use

Subtle surface Use #CDC3F5 for cards and hover fills. Tint 80

Avoid beside #5700A3 — 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 #2100A5 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: #2100A5;
  --color-base-rgb: 33 0 165;
  --color-base-oklch: oklch(33.9% 0.218 272.0);
  --color-50: #F3F0FE;
  --color-100: #DFD8FD;
  --color-200: #C0B1FC;
  --color-300: #9177F8;
  --color-400: #6746EC;
  --color-500: #4622D2;
  --color-600: #3C239F;
  --color-700: #2F1F70;
  --color-800: #221848;
  --color-900: #16112C;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  zaffre: {
    50: '#F3F0FE',
    100: '#DFD8FD',
    200: '#C0B1FC',
    300: '#9177F8',
    400: '#6746EC',
    500: '#4622D2',
    600: '#3C239F',
    700: '#2F1F70',
    800: '#221848',
    900: '#16112C',
  },
}

$base: #2100A5;
$base-ink: #FFFFFF;
$base-50: #F3F0FE;
$base-100: #DFD8FD;
$base-200: #C0B1FC;
$base-300: #9177F8;
$base-400: #6746EC;
$base-500: #4622D2;
$base-600: #3C239F;
$base-700: #2F1F70;
$base-800: #221848;
$base-900: #16112C;
$base-hover: #1A0083;
$base-subtle: #B3A3F3;

{
    "color": {
        "base": {
            "value": "#2100A5",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F0FE",
                "type": "color"
            },
            "100": {
                "value": "#DFD8FD",
                "type": "color"
            },
            "200": {
                "value": "#C0B1FC",
                "type": "color"
            },
            "300": {
                "value": "#9177F8",
                "type": "color"
            },
            "400": {
                "value": "#6746EC",
                "type": "color"
            },
            "500": {
                "value": "#4622D2",
                "type": "color"
            },
            "600": {
                "value": "#3C239F",
                "type": "color"
            },
            "700": {
                "value": "#2F1F70",
                "type": "color"
            },
            "800": {
                "value": "#221848",
                "type": "color"
            },
            "900": {
                "value": "#16112C",
                "type": "color"
            }
        }
    }
}

Palettes built on #2100A5

Color Lab

Pairs with #2100A5

UI roles & guardrails

In real applications

Scales

Every model

Export