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green · neutral

#55f521

a balanced, electric green · neutral · closest name: Lime

Token name suggestion: Studio Moss

RGB
85, 245, 33
HSL
105°, 91%, 55%
CMYK
65, 0, 87, 4
Luminance
0.6735

#55f521 is a balanced electric green, 105° on the wheel and 56/100 on the cool side. Put black text on it (14.47:1). As text it scores 1.45:1 on white — use #258606 instead. Nearest name is Lime, nearest Tailwind family is lime.

hsl(105 91% 55%)rgb(85 245 33)Base step 500AAA inkNeutral

At a glance

Every number on this page in one read: what #55f521 is made of, how bright it looks, and which way it leans.

Hex
#55f521
Hue
105°
green
Saturation
91%
electric
Lightness
55%
balanced
Brightness
96%
HSV value
Perceived
76%
weighted brightness
Luminance
0.6735
WCAG relative
Temperature
Neutral
56/100 cool
Color family
Green
Tone
Electric
Best ink
Black
14.47:1
Closest name
Lime
ΔE2000 2.8
Chroma
107.8
LCH, 0–130ish
OKLCH L
0.852
perceptual lightness
Tailwind
lime
500 · ΔE 10.5
Web-safe
#66FF33
nearest of 216
Where it sits
Hue105° of 360°
Saturation91%
Lightness55%
Saturation × lightness field

Left edge is grey, right edge is full chroma; top is white, bottom is black. The dot is #55f521.

Temperature
Warm ← → Cool56% cool

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

Luminance by channel
Red3%
Green97%
Blue0%

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

Every format

HEX#55f521
HEX (8-digit)#55f521ff
RGBrgb(85, 245, 33)
RGBArgba(85, 245, 33, 1)
HSLhsl(105, 91%, 55%)
HSV / HSBhsv(105, 87%, 96%)
HWBhwb(105 13% 4%)
CMYKcmyk(65%, 0%, 87%, 4%)
LABlab(85.7 -74.3 78.1)
LCHlch(85.7 107.8 133.6)
OKLCHoklch(0.852 0.266 140.1)
XYZ (D65)xyz(36.67, 67.34, 12.50)
Decimal5633313
Display P3color(display-p3 0.333 0.961 0.129)
Web-safe#66FF33

Copy-ready code

every platformclick to select
/* CSS */
color: #55f521;
background-color: #55f521;
/* CSS custom property */
--brand: #55f521;
/* Tailwind (arbitrary) */
class="text-[#55f521] bg-[#55f521]"
/* SCSS */
$brand: #55f521;
/* SwiftUI */
Color(red: 0.333, green: 0.961, blue: 0.129)
/* UIKit */
UIColor(red: 0.333, green: 0.961, blue: 0.129, alpha: 1)
/* Android XML */
<color name="brand">#55F521</color>
/* Android Compose */
Color(0xFF55F521)
/* Flutter */
Color(0xFF55F521)
/* Python / OpenCV (BGR) */
(33, 245, 85)
/* Python / PIL (RGB) */
(85, 245, 33)
/* Java AWT */
new Color(85, 245, 33)
/* .NET */
Color.FromArgb(255, 85, 245, 33)
/* OpenGL / Unity (0–1) */
(0.3333f, 0.9608f, 0.1294f, 1f)
/* LaTeX */
\definecolor{brand}{RGB}{85,245,33}
modern cssclick to select
/* mix without leaving CSS */
background: color-mix(in oklab, #55f521 85%, white);
border-color: color-mix(in oklab, #55f521 40%, transparent);
/* theme-aware in one line */
color: light-dark(#227A05, #D9EED3);
/* relative colour syntax */
--hover: hsl(from #55f521 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: #F4FDF2;
  --brand-100: #EAFBE4;
  --brand-200: #D0F9C3;
  --brand-300: #ADFA94;
  --brand-400: #84F85E;
  --brand-500: #55f521;
  --brand-600: #41EA0B;
  --brand-700: #36C309;
  --brand-800: #2C9C07;
  --brand-900: #23710A;
  --brand-950: #164606;
  --brand: #55f521;
  --brand-ink: #000000;
  --brand-surface: #F6FAF4;
  --brand-border: #CBEDC0;
  --brand-hover: #41E80A;
  --brand-pressed: #37C609;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand-surface: #182414;
    --brand-ink: #D9EED3;
  }
}
tailwind.config.jsclick to select
theme: {
  extend: {
    colors: {
      brand: {
        50: '#F4FDF2',
        100: '#EAFBE4',
        200: '#D0F9C3',
        300: '#ADFA94',
        400: '#84F85E',
        500: '#55f521',
        600: '#41EA0B',
        700: '#36C309',
        800: '#2C9C07',
        900: '#23710A',
        950: '#164606',
        DEFAULT: '#55f521',
      },
    },
  },
}
scss mapclick to select
$brand: (
  '50': #F4FDF2,
  '100': #EAFBE4,
  '200': #D0F9C3,
  '300': #ADFA94,
  '400': #84F85E,
  '500': #55f521,
  '600': #41EA0B,
  '700': #36C309,
  '800': #2C9C07,
  '900': #23710A,
  '950': #164606,
);
$brand-base: #55f521;
$brand-ink: #000000;

@function brand($step) { @return map-get($brand, $step); }
w3c design tokens (json)click to select
{
  "color": {
    "brand": {
      "50": { "$value": "#F4FDF2", "$type": "color" },
      "100": { "$value": "#EAFBE4", "$type": "color" },
      "200": { "$value": "#D0F9C3", "$type": "color" },
      "300": { "$value": "#ADFA94", "$type": "color" },
      "400": { "$value": "#84F85E", "$type": "color" },
      "500": { "$value": "#55f521", "$type": "color" },
      "600": { "$value": "#41EA0B", "$type": "color" },
      "700": { "$value": "#36C309", "$type": "color" },
      "800": { "$value": "#2C9C07", "$type": "color" },
      "900": { "$value": "#23710A", "$type": "color" },
      "950": { "$value": "#164606", "$type": "color" }
    },
    "brandInk": { "$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 #55f521 · 14.47:1
Use #000000AAA at every size.
Aa
12px
Aa
16px
Aa
24px
Aa
White text · 1.45:1
AA fail · AA large fail · AAA fail
Aa
Black text · 14.47:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #55f521 as text scores 1.45:1 on white and 14.47:1 on black.
Best tinted ink on it, if plain black or white feels flat: #227A05 at 3.75:1.

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
#258606 · 4.68:1
AA on white−27% L
#258606
The quick fox
#1C6404 · 7.31:1
AAA on white−34% L
#1C6404
The quick fox
#55f521 · 14.47:1
AA on blackalready passes
#55f521
The quick fox
#55f521 · 14.47:1
AAA on blackalready passes
#55f521

Large text — 24px regular or 18.66px bold and above — only needs 3:1, so #2FA808 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
#55f521 on white: 1.45:1
AA ✗ fail · AA-large · AAA
Aa
#55f521 on black: 14.47:1
AA ✓ pass · AA-large · AAA
Against the neutral ladder

Contrast is symmetric, so each row covers both directions: #55f521 as text on that neutral, and that neutral as text on #55f521.

NeutralRatioBoth directions
White1.45:1AaAa
Slate 501.39:1AaAa
Slate 1001.32:1AaAa
Slate 2001.18:1AaAa
Slate 3001.02:1AaAa
Slate 4001.77:1AaAa
Slate 5003.28:1AaAa
Slate 6005.22:1AaAa
Slate 7007.13:1AaAa
Slate 80010.08:1AaAa
Slate 90012.30:1AaAa
Black14.47:1AaAa
Colour vision deficiency
true color
protanopia · #FCDE00
deuteranopia · #E9D141
tritanopia · #39EDD1

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. #55f521 is pinned to step 500; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F4FDF2
#EAFBE4
#D0F9C3
#ADFA94
#84F85E
#55f521
#41EA0B
#36C309
#2C9C07
#23710A
#164606
Base = 500Lightest = 50 · #F4FDF2Darkest = 950 · #164606Text 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 0.066 140.1);
  --brand-100: oklch(0.94 0.106 140.1);
  --brand-200: oklch(0.88 0.160 140.1);
  --brand-300: oklch(0.80 0.207 140.1);
  --brand-400: oklch(0.72 0.245 140.1);
  --brand-500: oklch(0.64 0.266 140.1);
  --brand-600: oklch(0.56 0.266 140.1);
  --brand-700: oklch(0.48 0.250 140.1);
  --brand-800: oklch(0.40 0.223 140.1);
  --brand-900: oklch(0.32 0.186 140.1);
  --brand-950: oklch(0.24 0.146 140.1);
}

Colors that work with #55f521

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#F6FAF4
Tinted page background
Border#CBEDC0
Hairlines and dividers
Muted text#5E9B4B
Captions on the surface
Accent#8C1CFA
Second voice, not a rival
Dark variant#227A05
Hover, pressed, headers
Light variant#ECFEE7
Selected rows, tints
Dark surface#182414
Dark-mode background
Hover#41E80A
One step down in lightness
Pressed#37C609
Two steps down
Disabled#BCD0B6
Chroma pulled out
Focus ring#5FFF2B
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 #55f521

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
  • Brand accents, badges and data highlights
  • Chart series and data categories
Use with care
  • Text of any size on white — fails WCAG AA
  • Full-page backgrounds — tiring over long sessions
  • 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 #227A05
Safe as a 1px border on white
No — use #2FA808

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.

At this chroma the association is amplified — it will dominate anything placed beside it, so give it space and use it sparingly. The mid lightness keeps it versatile in both themes.

Worth knowing

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

Reads as
  • FormalityLow
  • EnergyHigh
  • Weight46/100
  • TemperatureNeutral
  • 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#C121F5
Analogous left#BFF521
Analogous right#21F557
Split-complement 1#5721F5
Split-complement 2#F521BF
Triadic 1#2155F5
Triadic 2#F52155
Tetradic#21BFF5
On the wheel
Base+30°−30°+120°+240°+180°105°

#55f521 sits at 105°. Every dot is a harmony position and links to its own page in the table alongside.

RGB percentages

Red33.3%
Green96.1%
Blue12.9%
R · 0–255
85
0x55
G · 0–255
245
0xf5
B · 0–255
33
0x21

CMYK percentages

Cyan65.3%
Magenta0.0%
Yellow86.5%
Key (black)3.9%

Total ink coverage is 156%. Most commercial presses cap around 300% — above that, sheets stop drying properly.

Color previews

#55f521 text on a black background

contrast 14.47:1

Card sample

#55f521 text on a white background

contrast 1.45:1

Card sample

#55f521 on grey

1.32:1

#55f521 on its own surface

1.38:1

#55f521 on its dark surface

11.12:1

CSS3 live lab

Text font color

The quick brown fox

color: #55f521;
Background color
Panel with #55f521 background
background-color: #55f521;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #55f521;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(85, 245, 33, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(85, 245, 33, 0.45);
Border & gradient
Gradient panel
border: 3px solid #55f521;
background: linear-gradient(135deg, #55f521, #21F57A);
Gradient text

Gradient headline

background: linear-gradient(90deg, #55f521, #21F5AF);
-webkit-background-clip: text;
color: transparent;
Focus ring
Focused control
outline: 2px solid #55f521;
outline-offset: 3px;
Underline & caret

Marked up text

text-decoration-color: #55f521;
caret-color: #55f521;
Left rule
Pull quote or callout
border-left: 4px solid #55f521;
Ring + tint
Selected chip
background: #ECFEE7;
box-shadow: inset 0 0 0 2px #55f521;
Conic badge
68%
background: conic-gradient(#55f521 68%, #e2e8f0 0);

Transparency

What each alpha value actually composites to. The top row is #55f521 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(85, 245, 33, 0.5)
rgb(85 245 33 / 50%)
#55f52180
hsl(105 91% 55% / 50%)
color-mix(in srgb, #55f521 50%, transparent)
Alpha8-digit hexFlat on white
10%#55f5211a#EEFEE9
20%#55f52133#DDFDD3
40%#55f52166#BBFBA6
60%#55f52199#99F97A
80%#55f521cc#77F74D

Gradients from #55f521

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, #82F85B, #55f521 45%, #227A05);
Duotone
A short hue run reads richer than a flat fill
background: linear-gradient(120deg, #55f521, #0BED7D);
Complement sweep
Loud — keep it behind large type only
background: linear-gradient(90deg, #55f521, #C121F5);
Spotlight
Hero panels and app headers
background: radial-gradient(120% 120% at 20% 0%, #98F979 0%, #55f521 45%, #227A05 100%);
Soft wash
Section backgrounds that stay readable
background: linear-gradient(180deg, #F6FAF4, #ffffff);
Mesh
Ambient background, no image weight
background: radial-gradient(60% 60% at 15% 20%, #DBF752 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #3EF67D 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #227A05 0%, transparent 65%), #55f521;

Monochromatic scale

Palettes built from #55f521

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.

#55f521 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

Sits outside most CMYK gamuts — expect a duller press result, or specify a spot ink.

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 14.47:1.

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.

#55f521, answered

What color is #55f521?

#55f521 is a balanced electric green, closest to Lime (ΔE2000 2.8). It sits at 105° on the hue wheel with 91% saturation and 55% lightness, which reads as neutral.

What is the RGB value of #55f521?

rgb(85, 245, 33) — 85 red, 245 green and 33 blue out of 255, or 33.3% / 96.1% / 12.9% by channel.

What is #55f521 in HSL and HSV?

hsl(105, 91%, 55%) and hsv(105, 87%, 96%). HSL is what CSS takes; HSV is what your design tool's picker shows, which is why the saturation numbers rarely match.

Is #55f521 a light or a dark color?

It is a light color. Relative luminance is 0.6735 and perceived brightness is 76%, so black text on it reaches 14.47:1.

Should I use black or white text on #55f521?

Black. It scores 14.47:1 against #55f521, versus 1.45:1 for white — AAA at any size.

Is #55f521 accessible on a white background?

#55f521 on white scores 1.45:1, which fails WCAG AA at every size. Darken it to #258606 to reach 4.5:1, or #1C6404 for 7:1.

What is the complementary color of #55f521?

#C121F5 sits directly opposite on the wheel. Softer options are the split-complements #5721F5 and #F521BF, which give the same contrast with far less vibration.

What colors go well with #55f521?

For interface work: #F6FAF4 as the surface, #CBEDC0 for borders, #5E9B4B for secondary text, #8C1CFA as an accent and #227A05 for hover and pressed states. For a palette, the analogous pair #BFF521 and #21F557 stays calm, while #C121F5 is the loudest partner.

What is #55f521 in CMYK for printing?

cmyk(65%, 0%, 87%, 4%). This is a screen-to-ink approximation — a color this saturated sits outside most CMYK gamuts and will print duller than it looks here.

Is #55f521 warm or cool?

Neutral — it scores 56 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #A3F521; nudged cooler, #1FF739.

Which Tailwind color is closest to #55f521?

The lime family — its 500 step is #84cc16, ΔE2000 10.5 away. That is a visible difference, so define #55f521 as a custom token rather than reaching for the built-in.

How do I use #55f521 in Tailwind CSS?

Inline it as an arbitrary value with bg-[#55f521] or text-[#55f521], 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 #55f521 with 50% opacity?

rgba(85, 245, 33, 0.5), or #55f52180 in eight-digit hex. Over white that composites to #AAFA90; over black, #2B7B11.

Is #55f521 a web-safe color?

No. The nearest web-safe colour is #66FF33, ΔE2000 2.3 away. The palette only matters for legacy displays and some email clients now.

What does the color #55f521 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 #55f521?

The safest is same-hue elevation: linear-gradient(135deg, #82F85B, #55f521 45%, #227A05). For more colour, a short hue run to #0BED7D keeps it rich without turning muddy.

Work with #55f521 in the Color Lab

Every tool opens with this colour already loaded.

Every value on this page is computed from #55f521 at request time — conversions, contrast ratios and ΔE distances are calculated, never looked up.