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green · cool

#1bb521

a dark, vivid green · cool · closest name: Lime Green

Token name suggestion: Shadow Moss

RGB
27, 181, 33
HSL
122°, 74%, 41%
CMYK
85, 0, 82, 29
Luminance
0.3339

#1bb521 is a dark vivid green, 122° on the wheel and 63/100 on the cool side. Put black text on it (7.68:1). As text it scores 2.74:1 on white — use #148919 instead. Nearest name is Lime Green, nearest Tailwind family is green.

hsl(122 74% 41%)rgb(27 181 33)Base step 700AAA inkCool

At a glance

Every number on this page in one read: what #1bb521 is made of, how bright it looks, and which way it leans.

Hex
#1bb521
Hue
122°
green
Saturation
74%
vivid
Lightness
41%
dark
Brightness
71%
HSV value
Perceived
55%
weighted brightness
Luminance
0.3339
WCAG relative
Temperature
Cool
63/100 cool
Color family
Green
Tone
Vivid
Best ink
Black
7.68:1
Closest name
Lime Green
ΔE2000 6.5
Chroma
86.7
LCH, 0–130ish
OKLCH L
0.673
perceptual lightness
Tailwind
green
500 · ΔE 7.3
Web-safe
#33CC33
nearest of 216
Where it sits
Hue122° of 360°
Saturation74%
Lightness41%
Saturation × lightness field

Left edge is grey, right edge is full chroma; top is white, bottom is black. The dot is #1bb521.

Temperature
Warm ← → Cool63% cool

Reads cool. Warm and cool siblings keep the same lightness, so you can swap one in without redoing your contrast maths.

Luminance by channel
Red1%
Green99%
Blue0%

Green carries most of what the eye calls brightness — that is why WCAG weights it 0.7152.

Every format

HEX#1bb521
HEX (8-digit)#1bb521ff
RGBrgb(27, 181, 33)
RGBArgba(27, 181, 33, 1)
HSLhsl(122, 74%, 41%)
HSV / HSBhsv(122, 85%, 71%)
HWBhwb(122 11% 29%)
CMYKcmyk(85%, 0%, 82%, 29%)
LABlab(64.5 -63.8 58.7)
LCHlch(64.5 86.7 137.4)
OKLCHoklch(0.673 0.216 143.0)
XYZ (D65)xyz(17.25, 33.39, 6.97)
Decimal1815841
Display P3color(display-p3 0.106 0.710 0.129)
Web-safe#33CC33

Copy-ready code

every platformclick to select
/* CSS */
color: #1bb521;
background-color: #1bb521;
/* CSS custom property */
--brand: #1bb521;
/* Tailwind (arbitrary) */
class="text-[#1bb521] bg-[#1bb521]"
/* SCSS */
$brand: #1bb521;
/* SwiftUI */
Color(red: 0.106, green: 0.710, blue: 0.129)
/* UIKit */
UIColor(red: 0.106, green: 0.710, blue: 0.129, alpha: 1)
/* Android XML */
<color name="brand">#1BB521</color>
/* Android Compose */
Color(0xFF1BB521)
/* Flutter */
Color(0xFF1BB521)
/* Python / OpenCV (BGR) */
(33, 181, 27)
/* Python / PIL (RGB) */
(27, 181, 33)
/* Java AWT */
new Color(27, 181, 33)
/* .NET */
Color.FromArgb(255, 27, 181, 33)
/* OpenGL / Unity (0–1) */
(0.1059f, 0.7098f, 0.1294f, 1f)
/* LaTeX */
\definecolor{brand}{RGB}{27,181,33}
modern cssclick to select
/* mix without leaving CSS */
background: color-mix(in oklab, #1bb521 85%, white);
border-color: color-mix(in oklab, #1bb521 40%, transparent);
/* theme-aware in one line */
color: light-dark(#116F14, #D3EED4);
/* relative colour syntax */
--hover: hsl(from #1bb521 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.

css custom propertiesclick to select
:root {
  --brand-50: #F3FCF3;
  --brand-100: #E7F9E8;
  --brand-200: #C8F3CA;
  --brand-300: #9DF0A1;
  --brand-400: #6DE971;
  --brand-500: #3CE242;
  --brand-600: #20D527;
  --brand-700: #1bb521;
  --brand-800: #158E1A;
  --brand-900: #146717;
  --brand-950: #0C400E;
  --brand: #1bb521;
  --brand-ink: #000000;
  --brand-surface: #F4FAF5;
  --brand-border: #C0EDC1;
  --brand-hover: #16961B;
  --brand-pressed: #127716;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand-surface: #142414;
    --brand-ink: #D3EED4;
  }
}
tailwind.config.jsclick to select
theme: {
  extend: {
    colors: {
      brand: {
        50: '#F3FCF3',
        100: '#E7F9E8',
        200: '#C8F3CA',
        300: '#9DF0A1',
        400: '#6DE971',
        500: '#3CE242',
        600: '#20D527',
        700: '#1bb521',
        800: '#158E1A',
        900: '#146717',
        950: '#0C400E',
        DEFAULT: '#1bb521',
      },
    },
  },
}
scss mapclick to select
$brand: (
  '50': #F3FCF3,
  '100': #E7F9E8,
  '200': #C8F3CA,
  '300': #9DF0A1,
  '400': #6DE971,
  '500': #3CE242,
  '600': #20D527,
  '700': #1bb521,
  '800': #158E1A,
  '900': #146717,
  '950': #0C400E,
);
$brand-base: #1bb521;
$brand-ink: #000000;

@function brand($step) { @return map-get($brand, $step); }
w3c design tokens (json)click to select
{
  "color": {
    "brand": {
      "50": { "$value": "#F3FCF3", "$type": "color" },
      "100": { "$value": "#E7F9E8", "$type": "color" },
      "200": { "$value": "#C8F3CA", "$type": "color" },
      "300": { "$value": "#9DF0A1", "$type": "color" },
      "400": { "$value": "#6DE971", "$type": "color" },
      "500": { "$value": "#3CE242", "$type": "color" },
      "600": { "$value": "#20D527", "$type": "color" },
      "700": { "$value": "#1bb521", "$type": "color" },
      "800": { "$value": "#158E1A", "$type": "color" },
      "900": { "$value": "#146717", "$type": "color" },
      "950": { "$value": "#0C400E", "$type": "color" }
    },
    "brandInk": { "$value": "#000000", "$type": "color" }
  }
}

Best text color

Only one of black and white can be right. This is the one, with the number that proves it.

Readable at a glance#000000 on #1bb521 · 7.68:1
Use #000000AAA at every size.
Aa
12px
Aa
16px
Aa
24px
Aa
White text · 2.74:1
AA fail · AA large fail · AAA fail
Aa
Black text · 7.68:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #1bb521 as text scores 2.74:1 on white and 7.68:1 on black.
Best tinted ink on it, if plain black or white feels flat: #116F14 at 2.32:1.

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.

The quick fox
#148919 · 4.54:1
AA on white−10% L
#148919
The quick fox
#0F6512 · 7.27:1
AAA on white−18% L
#0F6512
The quick fox
#1bb521 · 7.68:1
AA on blackalready passes
#1bb521
The quick fox
#1bb521 · 7.68:1
AAA on blackalready passes
#1bb521

Large text — 24px regular or 18.66px bold and above — only needs 3:1, so #1AAC1F 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

Aa
#1bb521 on white: 2.74:1
AA ✗ fail · AA-large · AAA
Aa
#1bb521 on black: 7.68:1
AA ✓ pass · AA-large · AAA
Against the neutral ladder

Contrast is symmetric, so each row covers both directions: #1bb521 as text on that neutral, and that neutral as text on #1bb521.

NeutralRatioBoth directions
White2.74:1AaAa
Slate 502.61:1AaAa
Slate 1002.50:1AaAa
Slate 2002.22:1AaAa
Slate 3001.84:1AaAa
Slate 4001.07:1AaAa
Slate 5001.74:1AaAa
Slate 6002.77:1AaAa
Slate 7003.79:1AaAa
Slate 8005.35:1AaAa
Slate 9006.53:1AaAa
Black7.68:1AaAa
Colour vision deficiency
true color
protanopia · #B9A300
deuteranopia · #A99834
tritanopia · #00B09A

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. #1bb521 is pinned to step 700; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F3FCF3
#E7F9E8
#C8F3CA
#9DF0A1
#6DE971
#3CE242
#20D527
#1bb521
#158E1A
#146717
#0C400E
Base = 700Lightest = 50 · #F3FCF3Darkest = 950 · #0C400EText step on white = 900
Perceptual ramp — OKLCH

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.

50100200300400500600700800900950
oklch tokensclick to select
:root {
  --brand-50: oklch(0.97 0.054 143.0);
  --brand-100: oklch(0.94 0.087 143.0);
  --brand-200: oklch(0.88 0.130 143.0);
  --brand-300: oklch(0.80 0.169 143.0);
  --brand-400: oklch(0.72 0.199 143.0);
  --brand-500: oklch(0.64 0.216 143.0);
  --brand-600: oklch(0.56 0.216 143.0);
  --brand-700: oklch(0.48 0.204 143.0);
  --brand-800: oklch(0.40 0.182 143.0);
  --brand-900: oklch(0.32 0.152 143.0);
  --brand-950: oklch(0.24 0.119 143.0);
}

Colors that work with #1bb521

Not a palette — a role sheet. Each swatch answers one question you will hit while building the component.

Text on it#000000
Black wins here
Surface#F4FAF5
Tinted page background
Border#C0EDC1
Hairlines and dividers
Muted text#4B9B4E
Captions on the surface
Accent#9717B9
Second voice, not a rival
Dark variant#116F14
Hover, pressed, headers
Light variant#E9FCEA
Selected rows, tints
Dark surface#142414
Dark-mode background
Hover#16961B
One step down in lightness
Pressed#127716
Two steps down
Disabled#8BB58D
Chroma pulled out
Focus ring#12D21A
Offset from the fill so it reads
Light mode
Everything in its place

Surface, border, heading and body all derive from this one hue, so the screen stays coherent without a second palette.

Primary actionSecondaryBadge
Dark mode
Same hue, inverted

Lightness flips, hue holds. The accent stays the anchor in both themes.

Primary actionSecondaryAccent

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.

Buttons and states
Save changesHoverPressedDisabled
OutlineSubtleLinkFocused
Form field
you@company.com

Focus ring uses the light variant so the field still reads as one shape.

Send me product updates
Notice
Your export is ready

The file stays available for seven days. Download it before it expires.

NewBetaDraft
Data
Storage used68%
Acme LtdActive
NorthwindTrial
GlobexActive

How to use #1bb521

Derived from its contrast, chroma and lightness — not from taste.

Works well for
  • Text and icons on dark surfaces
  • Primary buttons and calls to action
  • Focus rings, active and selected states
  • Headers, footers and dark-mode surfaces
  • Brand accents, badges and data highlights
Use with care
  • Text of any size on white — fails WCAG AA
  • Full-page backgrounds — tiring over long sessions
  • 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
Minimum size as text on white
Not as text
Safe as a fill behind white type
No — use #116F14
Safe as a 1px border on white
No — use #1AAC1F

Meaning and mood

What a colour in this family tends to signal, and how this particular chroma and lightness change the reading.

safegrowingnaturalpermissive

Green means go, well, and grown. It carries finance, sustainability and health with almost no explanation needed.

This is a confident chroma: strong enough to lead a brand, restrained enough to live in an interface all day. The low lightness adds weight and formality.

Worth knowing

Red/green pairs are the most common colour-blindness failure — never let the two carry meaning alone.

Reads as
  • FormalityHigh
  • EnergyMedium-high
  • Weight59/100
  • TemperatureCool
  • ApproachabilityBalanced

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#B51BAF
Analogous left#62B51B
Analogous right#1BB56E
Split-complement 1#6E1BB5
Split-complement 2#B51B62
Triadic 1#211BB5
Triadic 2#B5211B
Tetradic#1B62B5
On the wheel
Base+30°−30°+120°+240°+180°122°

#1bb521 sits at 122°. Every dot is a harmony position and links to its own page in the table alongside.

RGB percentages

Red10.6%
Green71.0%
Blue12.9%
R · 0–255
27
0x1b
G · 0–255
181
0xb5
B · 0–255
33
0x21

CMYK percentages

Cyan85.1%
Magenta0.0%
Yellow81.8%
Key (black)29.0%

Total ink coverage is 196%. Most commercial presses cap around 300% — above that, sheets stop drying properly.

Color previews

#1bb521 text on a black background

contrast 7.68:1

Card sample

#1bb521 text on a white background

contrast 2.74:1

Card sample

#1bb521 on grey

2.50:1

#1bb521 on its own surface

2.58:1

#1bb521 on its dark surface

5.94:1

CSS3 live lab

Text font color

The quick brown fox

color: #1bb521;
Background color
Panel with #1bb521 background
background-color: #1bb521;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #1bb521;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(27, 181, 33, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(27, 181, 33, 0.45);
Border & gradient
Gradient panel
border: 3px solid #1bb521;
background: linear-gradient(135deg, #1bb521, #1BB588);
Gradient text

Gradient headline

background: linear-gradient(90deg, #1bb521, #1BB5AE);
-webkit-background-clip: text;
color: transparent;
Focus ring
Focused control
outline: 2px solid #1bb521;
outline-offset: 3px;
Underline & caret

Marked up text

text-decoration-color: #1bb521;
caret-color: #1bb521;
Left rule
Pull quote or callout
border-left: 4px solid #1bb521;
Ring + tint
Selected chip
background: #E9FCEA;
box-shadow: inset 0 0 0 2px #1bb521;
Conic badge
68%
background: conic-gradient(#1bb521 68%, #e2e8f0 0);

Transparency

What each alpha value actually composites to. The top row is #1bb521 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.

alpha in every syntaxclick to select
rgba(27, 181, 33, 0.5)
rgb(27 181 33 / 50%)
#1bb52180
hsl(122 74% 41% / 50%)
color-mix(in srgb, #1bb521 50%, transparent)
Alpha8-digit hexFlat on white
10%#1bb5211a#E8F8E9
20%#1bb52133#D1F0D3
40%#1bb52166#A4E1A6
60%#1bb52199#76D37A
80%#1bb521cc#49C44D

Gradients from #1bb521

Six recipes, each built from this hex and shown with the exact CSS that produced it.

Elevation
Same hue, three lightnesses — safe anywhere
background: linear-gradient(135deg, #2EE034, #1bb521 45%, #116F14);
Duotone
A short hue run reads richer than a flat fill
background: linear-gradient(120deg, #1bb521, #179A7F);
Complement sweep
Loud — keep it behind large type only
background: linear-gradient(90deg, #1bb521, #B51BAF);
Spotlight
Hero panels and app headers
background: radial-gradient(120% 120% at 20% 0%, #48E44E 0%, #1bb521 45%, #116F14 100%);
Soft wash
Section backgrounds that stay readable
background: linear-gradient(180deg, #F4FAF5, #ffffff);
Mesh
Ambient background, no image weight
background: radial-gradient(60% 60% at 15% 20%, #8ADE25 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #1FD08D 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #116F14 0%, transparent 65%), #1bb521;

Monochromatic scale

Palettes built from #1bb521

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.

#1bb521 in the real world

Where a color in this family tends to land, and the interface roles it is usually asked to play.

Industries
SustainabilityFinanceHealth and wellnessAgriculture
Common UI roles
ButtonsLinksFocus statesCharts
Print note

Converts to four-color process without much drama. Proof it anyway.

On screens

Holds up across typical panel gamma. Still worth checking on an uncalibrated laptop, where mid-tones shift most.

In dark mode

Usable as-is on a dark surface at 7.68:1.

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.

#1bb521, answered

What color is #1bb521?

#1bb521 is a dark vivid green, closest to Lime Green (ΔE2000 6.5). It sits at 122° on the hue wheel with 74% saturation and 41% lightness, which reads as cool.

What is the RGB value of #1bb521?

rgb(27, 181, 33) — 27 red, 181 green and 33 blue out of 255, or 10.6% / 71% / 12.9% by channel.

What is #1bb521 in HSL and HSV?

hsl(122, 74%, 41%) and hsv(122, 85%, 71%). HSL is what CSS takes; HSV is what your design tool's picker shows, which is why the saturation numbers rarely match.

Is #1bb521 a light or a dark color?

It is a mid-tone. Relative luminance is 0.3339 and perceived brightness is 55%, so black text on it reaches 7.68:1.

Should I use black or white text on #1bb521?

Black. It scores 7.68:1 against #1bb521, versus 2.74:1 for white — AAA at any size.

Is #1bb521 accessible on a white background?

#1bb521 on white scores 2.74:1, which fails WCAG AA at every size. Darken it to #148919 to reach 4.5:1, or #0F6512 for 7:1.

What is the complementary color of #1bb521?

#B51BAF sits directly opposite on the wheel. Softer options are the split-complements #6E1BB5 and #B51B62, which give the same contrast with far less vibration.

What colors go well with #1bb521?

For interface work: #F4FAF5 as the surface, #C0EDC1 for borders, #4B9B4E for secondary text, #9717B9 as an accent and #116F14 for hover and pressed states. For a palette, the analogous pair #62B51B and #1BB56E stays calm, while #B51BAF is the loudest partner.

What is #1bb521 in CMYK for printing?

cmyk(85%, 0%, 82%, 29%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #1bb521 warm or cool?

Cool — it scores 63 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #4EB51B; nudged cooler, #19B759.

Which Tailwind color is closest to #1bb521?

The green family — its 500 step is #22c55e, ΔE2000 7.3 away. That is a visible difference, so define #1bb521 as a custom token rather than reaching for the built-in.

How do I use #1bb521 in Tailwind CSS?

Inline it as an arbitrary value with bg-[#1bb521] or text-[#1bb521], 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 #1bb521 with 50% opacity?

rgba(27, 181, 33, 0.5), or #1bb52180 in eight-digit hex. Over white that composites to #8DDA90; over black, #0E5B11.

Is #1bb521 a web-safe color?

No. The nearest web-safe colour is #33CC33, ΔE2000 6.2 away. The palette only matters for legacy displays and some email clients now.

What does the color #1bb521 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 chroma the effect is amplified — it will dominate whatever sits beside it.

What gradient works with #1bb521?

The safest is same-hue elevation: linear-gradient(135deg, #2EE034, #1bb521 45%, #116F14). For more colour, a short hue run to #179A7F keeps it rich without turning muddy.

Work with #1bb521 in the Color Lab

Every tool opens with this colour already loaded.

Every value on this page is computed from #1bb521 at request time — conversions, contrast ratios and ΔE distances are calculated, never looked up.