#183e21
a deep, soft green · cool · closest name: Dark Slate Gray
Token name suggestion: Abyss Jade
#183e21 is a deep soft green, 134° on the wheel and 68/100 on the cool side. Put white text on it (12.00:1). As text it scores 12.00:1 on white — safe at any size. Nearest name is Dark Slate Gray, nearest Tailwind family is neutral.
At a glance
Every number on this page in one read: what #183e21 is made of, how bright it looks, and which way it leans.
Left edge is grey, right edge is full chroma; top is white, bottom is black. The dot is #183e21.
Reads cool. Warm and cool siblings keep the same lightness, so you can swap one in without redoing your contrast maths.
Green carries most of what the eye calls brightness — that is why WCAG weights it 0.7152.
Every format
| HEX | #183e21 |
| HEX (8-digit) | #183e21ff |
| RGB | rgb(24, 62, 33) |
| RGBA | rgba(24, 62, 33, 1) |
| HSL | hsl(134, 44%, 17%) |
| HSV / HSB | hsv(134, 61%, 24%) |
| HWB | hwb(134 9% 76%) |
| CMYK | cmyk(61%, 0%, 47%, 76%) |
| LAB | lab(22.8 -21.2 13.8) |
| LCH | lch(22.8 25.3 146.8) |
| OKLCH | oklch(0.327 0.067 149.2) |
| XYZ (D65) | xyz(2.37, 3.75, 2.04) |
| Decimal | 1588769 |
| Display P3 | color(display-p3 0.094 0.243 0.129) |
| Web-safe | #003333 |
Copy-ready code
/* CSS */
color: #183e21;
background-color: #183e21;
/* CSS custom property */
--brand: #183e21;
/* Tailwind (arbitrary) */
class="text-[#183e21] bg-[#183e21]"
/* SCSS */
$brand: #183e21;
/* SwiftUI */
Color(red: 0.094, green: 0.243, blue: 0.129)
/* UIKit */
UIColor(red: 0.094, green: 0.243, blue: 0.129, alpha: 1)
/* Android XML */
<color name="brand">#183E21</color>
/* Android Compose */
Color(0xFF183E21)
/* Flutter */
Color(0xFF183E21)
/* Python / OpenCV (BGR) */
(33, 62, 24)
/* Python / PIL (RGB) */
(24, 62, 33)
/* Java AWT */
new Color(24, 62, 33)
/* .NET */
Color.FromArgb(255, 24, 62, 33)
/* OpenGL / Unity (0–1) */
(0.0941f, 0.2431f, 0.1294f, 1f)
/* LaTeX */
\definecolor{brand}{RGB}{24,62,33}/* mix without leaving CSS */ background: color-mix(in oklab, #183e21 85%, white); border-color: color-mix(in oklab, #183e21 40%, transparent); /* theme-aware in one line */ color: light-dark(#245C31, #D3EED9); /* relative colour syntax */ --hover: hsl(from #183e21 h s calc(l - 7));
Design tokens
The same ramp in the four formats a team actually needs. Paste one and the whole palette lands with it.
:root {
--brand-50: #F5FAF6;
--brand-100: #EAF5ED;
--brand-200: #D1EBD7;
--brand-300: #AEE0BA;
--brand-400: #86D097;
--brand-500: #5DC075;
--brand-600: #44B15E;
--brand-700: #39934E;
--brand-800: #2E763F;
--brand-900: #245630;
--brand-950: #183e21;
--brand: #183e21;
--brand-ink: #ffffff;
--brand-surface: #F4FAF6;
--brand-border: #C4E8CD;
--brand-hover: #0E2413;
--brand-pressed: #040B06;
}
@media (prefers-color-scheme: dark) {
:root {
--brand-surface: #142418;
--brand-ink: #D3EED9;
}
}theme: {
extend: {
colors: {
brand: {
50: '#F5FAF6',
100: '#EAF5ED',
200: '#D1EBD7',
300: '#AEE0BA',
400: '#86D097',
500: '#5DC075',
600: '#44B15E',
700: '#39934E',
800: '#2E763F',
900: '#245630',
950: '#183e21',
DEFAULT: '#183e21',
},
},
},
}$brand: (
'50': #F5FAF6,
'100': #EAF5ED,
'200': #D1EBD7,
'300': #AEE0BA,
'400': #86D097,
'500': #5DC075,
'600': #44B15E,
'700': #39934E,
'800': #2E763F,
'900': #245630,
'950': #183e21,
);
$brand-base: #183e21;
$brand-ink: #ffffff;
@function brand($step) { @return map-get($brand, $step); }{
"color": {
"brand": {
"50": { "$value": "#F5FAF6", "$type": "color" },
"100": { "$value": "#EAF5ED", "$type": "color" },
"200": { "$value": "#D1EBD7", "$type": "color" },
"300": { "$value": "#AEE0BA", "$type": "color" },
"400": { "$value": "#86D097", "$type": "color" },
"500": { "$value": "#5DC075", "$type": "color" },
"600": { "$value": "#44B15E", "$type": "color" },
"700": { "$value": "#39934E", "$type": "color" },
"800": { "$value": "#2E763F", "$type": "color" },
"900": { "$value": "#245630", "$type": "color" },
"950": { "$value": "#183e21", "$type": "color" }
},
"brandInk": { "$value": "#ffffff", "$type": "color" }
}
}Best text color
Only one of black and white can be right. This is the one, with the number that proves it.
Make it accessible
A contrast checker tells you that you failed. This tells you what to ship instead — same hue, same saturation, lightness moved only as far as WCAG demands.
Large text — 24px regular or 18.66px bold and above — only needs 3:1, so #183E21 is enough for headings on white. Non-text elements such as icons, chart strokes and focus rings also sit at 3:1 under WCAG 2.2 (1.4.11).
Accessibility — WCAG contrast
Contrast is symmetric, so each row covers both directions: #183e21 as text on that neutral, and that neutral as text on #183e21.
| Neutral | Ratio | Verdict | Both directions |
|---|---|---|---|
| White#ffffff | 12.00:1 | AAAA lgAAA | AaAa |
| Slate 50#f8fafc | 11.47:1 | AAAA lgAAA | AaAa |
| Slate 100#f1f5f9 | 10.95:1 | AAAA lgAAA | AaAa |
| Slate 200#e2e8f0 | 9.73:1 | AAAA lgAAA | AaAa |
| Slate 300#cbd5e1 | 8.08:1 | AAAA lgAAA | AaAa |
| Slate 400#94a3b8 | 4.68:1 | AAAA lgAAA | AaAa |
| Slate 500#64748b | 2.52:1 | AAAA lgAAA | AaAa |
| Slate 600#475569 | 1.58:1 | AAAA lgAAA | AaAa |
| Slate 700#334155 | 1.16:1 | AAAA lgAAA | AaAa |
| Slate 800#1e293b | 1.22:1 | AAAA lgAAA | AaAa |
| Slate 900#0f172a | 1.49:1 | AAAA lgAAA | AaAa |
| Black#000000 | 1.75:1 | AAAA lgAAA | AaAa |
Roughly one man in twelve has some form of colour vision deficiency. If any of the three panels above is hard to tell apart from a neighbouring colour in your palette, add a shape, an icon or a label so the meaning does not rest on hue alone.
Color scale — 50 to 950
A Tailwind-shaped ramp built around this exact hex. #183e21 is pinned to step 950; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.
The same eleven steps expressed in OKLCH, where equal lightness numbers actually look equally spaced. HSL ramps go muddy in the yellows and washed out in the blues; this one does not. Modern browsers render it natively — the hex ramp above is the fallback.
:root {
--brand-50: oklch(0.97 0.017 149.2);
--brand-100: oklch(0.94 0.027 149.2);
--brand-200: oklch(0.88 0.040 149.2);
--brand-300: oklch(0.80 0.052 149.2);
--brand-400: oklch(0.72 0.062 149.2);
--brand-500: oklch(0.64 0.067 149.2);
--brand-600: oklch(0.56 0.067 149.2);
--brand-700: oklch(0.48 0.063 149.2);
--brand-800: oklch(0.40 0.056 149.2);
--brand-900: oklch(0.32 0.047 149.2);
--brand-950: oklch(0.24 0.037 149.2);
}Colors that work with #183e21
Not a palette — a role sheet. Each swatch answers one question you will hit while building the component.
Surface, border, heading and body all derive from this one hue, so the screen stays coherent without a second palette.
Lightness flips, hue holds. The accent stays the anchor in both themes.
In real components
The same eight roles, wired into the interface patterns you will actually build with them. Every state below is a computed value, not a mock-up.
Focus ring uses the light variant so the field still reads as one shape.
The file stays available for seven days. Download it before it expires.
How to use #183e21
Derived from its contrast, chroma and lightness — not from taste.
- ✓Body text and links on white
- ✓Charts, tags and secondary surfaces
- ✓Headers, footers and dark-mode surfaces
- ✓Brand accents, badges and data highlights
- ⚠Text on black or near-black surfaces
- ⚠Black text placed on it
- ⚠Status meaning — pair it with an icon or label, never colour alone
- ⚠Pairing with a same-lightness hue — edges vibrate
Meaning and mood
What a colour in this family tends to signal, and how this particular chroma and lightness change the reading.
Green means go, well, and grown. It carries finance, sustainability and health with almost no explanation needed.
The muted chroma softens the association — it reads considered rather than loud, which suits long-form and data-heavy screens. The low lightness adds weight and formality.
Red/green pairs are the most common colour-blindness failure — never let the two carry meaning alone.
- FormalityHigh
- EnergyMedium
- Weight83/100
- TemperatureCool
- ApproachabilityReserved
Colour associations are cultural and vary by market. Treat these as a starting point for a conversation with your audience, not a finding about them.
Similar colors
One move away from this hex in each direction. Every swatch is its own page.
Color relationships
The wheel positions with their names attached, so you can grab the one you actually need.
| Complementary | #3E1835 | Directly opposite — maximum tension | |
| Analogous left | #223E18 | Neighbour, quieter | |
| Analogous right | #183E34 | Neighbour, quieter | |
| Split-complement 1 | #34183E | Contrast without the clash | |
| Split-complement 2 | #3E1822 | Contrast without the clash | |
| Triadic 1 | #21183E | Even thirds — balanced and loud | |
| Triadic 2 | #3E2118 | Even thirds — balanced and loud | |
| Tetradic | #18223E | Fourth corner of the square scheme |
#183e21 sits at 134°. Every dot is a harmony position and links to its own page in the table alongside.
RGB percentages
CMYK percentages
Total ink coverage is 184%. Most commercial presses cap around 300% — above that, sheets stop drying properly.
Color previews
#183e21 text on a black background
contrast 1.75:1
#183e21 text on a white background
contrast 12.00:1
#183e21 on grey
10.95:1
#183e21 on its own surface
11.34:1
#183e21 on its dark surface
1.35:1
CSS3 live lab
The quick brown fox
color: #183e21;
background-color: #183e21;
Glowing headline
text-shadow: 2px 2px 8px #183e21;
Soft neon halo
text-shadow: 0 0 14px rgba(24, 62, 33, 0.45);
box-shadow: 0 12px 32px -8px rgba(24, 62, 33, 0.45);
border: 3px solid #183e21; background: linear-gradient(135deg, #183e21, #183E3A);
Gradient headline
background: linear-gradient(90deg, #183e21, #18383E); -webkit-background-clip: text; color: transparent;
outline: 2px solid #183e21; outline-offset: 3px;
Marked up text
text-decoration-color: #183e21; caret-color: #183e21;
border-left: 4px solid #183e21;
background: #EDF8EF; box-shadow: inset 0 0 0 2px #183e21;
background: conic-gradient(#183e21 68%, #e2e8f0 0);
Transparency
What each alpha value actually composites to. The top row is #183e21 over white; the bottom row is the same alpha over a checkerboard, so you can see what survives on a photo or a video.
Bottom row of hexes is the flattened result over white — use those when a design tool refuses transparency, or when you need a solid fallback.
rgba(24, 62, 33, 0.5) rgb(24 62 33 / 50%) #183e2180 hsl(134 44% 17% / 50%) color-mix(in srgb, #183e21 50%, transparent)
| Alpha | 8-digit hex | Flat on white |
|---|---|---|
| 10% | #183e211a | #E8ECE9 |
| 20% | #183e2133 | #D1D8D3 |
| 40% | #183e2166 | #A3B2A6 |
| 60% | #183e2199 | #748B7A |
| 80% | #183e21cc | #46654D |
Gradients from #183e21
Six recipes, each built from this hex and shown with the exact CSS that produced it.
background: linear-gradient(135deg, #296A39, #183e21 45%, #245C31);
background: linear-gradient(120deg, #183e21, #102828);
background: linear-gradient(90deg, #183e21, #3E1835);
background: radial-gradient(120% 120% at 20% 0%, #328044 0%, #183e21 45%, #245C31 100%);
background: linear-gradient(180deg, #F4FAF6, #ffffff);
background: radial-gradient(60% 60% at 15% 20%, #3B6326 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #21544B 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #245C31 0%, transparent 65%), #183e21;
Monochromatic scale
Palettes built from #183e21
Shades — darker
Tints — lighter
Tones — desaturated
Color harmonies
Nearest named colors
Ranked with CIEDE2000 across all 139 CSS keywords. Under ΔE 2 the eye stops telling them apart; over ΔE 10 they are plainly different colors.
Closest color with a full write-up: Hunter Green (#355e3b) — ΔE2000 10.3 away, with its history, psychology and brand usage.
#183e21 in the real world
Where a color in this family tends to land, and the interface roles it is usually asked to play.
Converts to four-color process without much drama. Proof it anyway.
Very dark values collapse into each other on cheap panels — leave more lightness between your darkest steps than the numbers suggest.
Too dim on dark surfaces at 1.75:1 — lift it to #338446 for body text, or reserve it for fills.
Explore nearby colors
Small, deliberate steps away from this hex — useful when you are hunting for the version of a colour that finally feels right.
#183e21, answered
What color is #183e21?
#183e21 is a deep soft green, closest to Dark Slate Gray (ΔE2000 14.7). It sits at 134° on the hue wheel with 44% saturation and 17% lightness, which reads as cool.
What is the RGB value of #183e21?
rgb(24, 62, 33) — 24 red, 62 green and 33 blue out of 255, or 9.4% / 24.3% / 12.9% by channel.
What is #183e21 in HSL and HSV?
hsl(134, 44%, 17%) and hsv(134, 61%, 24%). HSL is what CSS takes; HSV is what your design tool's picker shows, which is why the saturation numbers rarely match.
Is #183e21 a light or a dark color?
It is a dark color. Relative luminance is 0.0375 and perceived brightness is 20%, so white text on it reaches 12.00:1.
Should I use black or white text on #183e21?
White. It scores 12.00:1 against #183e21, versus 1.75:1 for black — AAA at any size.
Is #183e21 accessible on a white background?
#183e21 on white scores 12.00:1, which clears AAA at every size.
What is the complementary color of #183e21?
#3E1835 sits directly opposite on the wheel. Softer options are the split-complements #34183E and #3E1822, which give the same contrast with far less vibration.
What colors go well with #183e21?
For interface work: #F4FAF6 as the surface, #C4E8CD for borders, #4B9B5E for secondary text, #3F1640 as an accent and #245C31 for hover and pressed states. For a palette, the analogous pair #223E18 and #183E34 stays calm, while #3E1835 is the loudest partner.
What is #183e21 in CMYK for printing?
cmyk(61%, 0%, 47%, 76%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.
Is #183e21 warm or cool?
Cool — it scores 68 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #1D3E18; nudged cooler, #173F2F.
Which Tailwind color is closest to #183e21?
The neutral family — its 500 step is #737373, ΔE2000 28.6 away. That is a visible difference, so define #183e21 as a custom token rather than reaching for the built-in.
How do I use #183e21 in Tailwind CSS?
Inline it as an arbitrary value with bg-[#183e21] or text-[#183e21], or register the whole ramp under theme.extend.colors.brand so you get bg-brand-500 and friends. The generated 50–950 scale on this page is ready to paste into your config.
What is #183e21 with 50% opacity?
rgba(24, 62, 33, 0.5), or #183e2180 in eight-digit hex. Over white that composites to #8C9F90; over black, #0C1F11.
Is #183e21 a web-safe color?
No. The nearest web-safe colour is #003333, ΔE2000 13.4 away. The palette only matters for legacy displays and some email clients now.
What does the color #183e21 mean?
As a green, it reads safe, growing, natural. Green means go, well, and grown. It carries finance, sustainability and health with almost no explanation needed. At this moderate chroma the association is present but not shouted.
What gradient works with #183e21?
The safest is same-hue elevation: linear-gradient(135deg, #296A39, #183e21 45%, #245C31). For more colour, a short hue run to #102828 keeps it rich without turning muddy.
Work with #183e21 in the Color Lab
Every tool opens with this colour already loaded.
Every value on this page is computed from #183e21 at request time — conversions, contrast ratios and ΔE distances are calculated, never looked up.