What color is #51B861?

#51B861 is a medium green. In RGB it is rgb(81, 184, 97), and in HSL hsl(129, 42%, 52%).

Is #51B861 accessible as text?

On white, #51B861 has a contrast ratio of 2.51:1 (fails WCAG AA for body text); on black it is 8.38:1 (passes). For text placed on #51B861, use black for the best readability.

What is the closest Tailwind color to #51B861?

The nearest Tailwind CSS token is emerald-500 (#00BC7D).

What colors go well with #51B861?

#51B861 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #B851A9. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #51B861 below.

Is #51B861 good for buttons?

#51B861 works well for buttons and highlights, but use black text on #51B861 — white text only reaches 2.51:1, below the 4.5:1 needed for normal-size labels.

Is #51B861 the same as CSS mediumseagreen?

No — #51B861 is not the CSS named color mediumseagreen, but mediumseagreen (#3CB371) is the closest CSS named color.

#51B861 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #51B861

Not just a swatch — here's how #51B861 works with other colors. Named schemes with #51B861 in its natural role, and a note on why the supporting colors balance it.

Botanical Studio Lead · 5 colors

Lead #51B861 Secondary #4C6B3C Accent #AD6C00 Surface #EEEAD6 Anchor #3C2F20

Medium Sea Green leads this botanical set among foliage greens and a terracotta accent, softened by cream and grounded in bark brown.

Coastal Morning Lead · 5 colors

Lead #51B861 Accent #A8C4BA Surface #E2D9BE Secondary #9AA09F Anchor #1A3648

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

Japanese Sand Base · 5 colors

Base #51B861 Surface #EEE9DC Highlight #F5F1E7 Secondary #B6B09F Ink #2B2723

Medium Sea Green sets a calm, sun-bleached base here, wrapped in bone and paper off-whites and a soft greige, with a single ink accent for wabi-sabi restraint.

Warm Autumn Interior Dominant · 5 colors

Dominant #51B861 Secondary #AD6C00 Accent #687C4C Surface #F2EDDD Anchor #3A2B1E

This palette keeps Medium Sea Green as the dominant warm neutral, balanced by muted terracotta and olive earth tones and grounded by a deep espresso anchor.

Minimal Editorial Surface · 5 colors

Surface #F7F4EF Accent #51B861 Secondary #B4D5B6 Support #989286 Ink #17140F

Medium Sea Green 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 Medium Sea Green carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #51B861 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 45/100

Neutral

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

Softness 50/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 31/100

Low

Airy and open — recedes, leaves the composition light.

Naturalness 81/100

Very high

Organic, earthy character — at home in wellness, food and craft brands.

Vintage feel 38/100

Low

A faint retro warmth without tipping into sepia.

Luxury 36/100

Low

Understated — leans refined without going austere.

Brand distinctiveness 61/100

High

Bold and ownable — memorable as a primary brand color.

UI accent fit 60/100

Moderate

Workable accent with care around contrast.

Surface fit 27/100

Low

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

Print safety 66/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #51B861

For UI

For branding

For interior

For fashion

People also use #51B861 with

Pistachio Verdigris Byzantine Platinum Hunter Green

UI roles & guardrails

Primary action Safe as a filled button with near-black label. AAA

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 7.4:1. Use

Subtle surface Use #DFEEE1 for cards and hover fills. Tint 80

Avoid beside #51B883 — 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 #51B861 at work across the surfaces designers actually ship.

Website / UI

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A working theme, generated in seconds.

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: #51B861;
  --color-base-rgb: 81 184 97;
  --color-base-oklch: oklch(70.1% 0.157 146.8);
  --color-50: #F4FBF5;
  --color-100: #E2F4E4;
  --color-200: #C5E7CA;
  --color-300: #9CD3A5;
  --color-400: #76BC81;
  --color-500: #559F61;
  --color-600: #477B4F;
  --color-700: #36583C;
  --color-800: #263B29;
  --color-900: #19241B;
  --color-on-base: #141310;
}

// tailwind.config.js
colors: {
  medium-sea-green: {
    50: '#F4FBF5',
    100: '#E2F4E4',
    200: '#C5E7CA',
    300: '#9CD3A5',
    400: '#76BC81',
    500: '#559F61',
    600: '#477B4F',
    700: '#36583C',
    800: '#263B29',
    900: '#19241B',
  },
}

$base: #51B861;
$base-ink: #141310;
$base-50: #F4FBF5;
$base-100: #E2F4E4;
$base-200: #C5E7CA;
$base-300: #9CD3A5;
$base-400: #76BC81;
$base-500: #559F61;
$base-600: #477B4F;
$base-700: #36583C;
$base-800: #263B29;
$base-900: #19241B;
$base-hover: #3E974B;
$base-subtle: #CFE6D2;

{
    "color": {
        "base": {
            "value": "#51B861",
            "type": "color"
        },
        "onBase": {
            "value": "#141310",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F4FBF5",
                "type": "color"
            },
            "100": {
                "value": "#E2F4E4",
                "type": "color"
            },
            "200": {
                "value": "#C5E7CA",
                "type": "color"
            },
            "300": {
                "value": "#9CD3A5",
                "type": "color"
            },
            "400": {
                "value": "#76BC81",
                "type": "color"
            },
            "500": {
                "value": "#559F61",
                "type": "color"
            },
            "600": {
                "value": "#477B4F",
                "type": "color"
            },
            "700": {
                "value": "#36583C",
                "type": "color"
            },
            "800": {
                "value": "#263B29",
                "type": "color"
            },
            "900": {
                "value": "#19241B",
                "type": "color"
            }
        }
    }
}