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#1cdf21

a balanced, electric green · cool · closest name: Lime Green

RGB
28, 223, 33
HSL
122°, 78%, 49%
CMYK
87, 0, 85, 13
Luminance
0.5313

At a glance

Every number on this page in one read: what #1cdf21 is made of, how bright it looks, and which way it leans.

Hex
#1cdf21
Hue
122°
green
Saturation
78%
electric
Lightness
49%
balanced
Brightness
87%
HSV value
Perceived
67%
weighted brightness
Luminance
0.5313
WCAG relative
Temperature
Cool
63/100 cool
Color family
Green
Tone
Electric
Best ink
Black
11.63:1
Closest name
Lime Green
ΔE2000 4.6
Where it sits
Hue122° of 360°
Saturation78%
Lightness49%
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.

Every format

HEX#1cdf21
RGBrgb(28, 223, 33)
HSLhsl(122, 78%, 49%)
CMYKcmyk(87%, 0%, 85%, 13%)
LABlab(78.0 -75.7 71.0)
LCHlch(78.0 103.8 136.9)
OKLCHoklch(0.785 0.258 142.8)
Decimal1892129
Display P3color(display-p3 0.110 0.875 0.129)

Copy-ready code

/* CSS */
color: #1cdf21;
background-color: #1cdf21;
/* Tailwind (arbitrary) */
class="text-[#1cdf21] bg-[#1cdf21]"
/* SCSS */
$brand: #1cdf21;
/* SwiftUI */
Color(red: 0.110, green: 0.875, blue: 0.129)
/* Android */
Color.parseColor("#1cdf21")
/* Flutter */
Color(0xFF1CDF21)
/* Python / OpenCV (BGR) */
(33, 223, 28)

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 #1cdf21 · 11.63:1
Use #000000AAA at every size.
Aa
White text · 1.81:1
AA fail · AA large fail · AAA fail
Aa
Black text · 11.63:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #1cdf21 as text scores 1.81:1 on white and 11.63:1 on black.

Accessibility — WCAG contrast

Aa
#1cdf21 on white: 1.81:1
AA ✗ fail · AA-large · AAA
Aa
#1cdf21 on black: 11.63:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #E4C900
deuteranopia · #D1BC3D
tritanopia · #00D8BE

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #1cdf21 is pinned to step 600; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F3FCF3
#E6F9E7
#C7F5C8
#9BF29D
#69EC6D
#38E63C
#1cdf21
#17B51B
#129115
#116914
#0B420C
Base = 600Lightest = 50 · #F3FCF3Darkest = 950 · #0B420C
:root {
  --brand-50: #F3FCF3;
  --brand-100: #E6F9E7;
  --brand-200: #C7F5C8;
  --brand-300: #9BF29D;
  --brand-400: #69EC6D;
  --brand-500: #38E63C;
  --brand-600: #1cdf21;
  --brand-700: #17B51B;
  --brand-800: #129115;
  --brand-900: #116914;
  --brand-950: #0B420C;
  --brand: #1cdf21;
  --brand-ink: #000000;
}

Colors that work with #1cdf21

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#F4FAF4
Tinted page background
Border#C0EDC1
Hairlines and dividers
Muted text#4B9B4D
Captions on the surface
Accent#B617E4
Second voice, not a rival
Dark variant#0E7111
Hover, pressed, headers
Light variant#E8FCE9
Selected rows, tints
Dark surface#142414
Dark-mode background
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

How to use #1cdf21

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
Use with care
  • Text of any size on white — fails WCAG AA
  • Full-page backgrounds — tiring over long sessions
  • Pairing with a same-lightness hue — edges vibrate

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#DF1CDA
Analogous left#79DF1C
Analogous right#1CDF82
Split-complement 1#821CDF
Split-complement 2#DF1C79
Triadic 1#211CDF
Triadic 2#DF211C
Tetradic#1C79DF

RGB percentages

Red11.0%
Green87.5%
Blue12.9%

CMYK percentages

Cyan87.4%
Magenta0.0%
Yellow85.2%
Key (black)12.5%

Color previews

#1cdf21 text on a black background

contrast 11.63:1

Card sample

#1cdf21 text on a white background

contrast 1.81:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #1cdf21;
Background color
Panel with #1cdf21 background
background-color: #1cdf21;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #1cdf21;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(28, 223, 33, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(28, 223, 33, 0.45);
Border & gradient
Gradient panel
border: 3px solid #1cdf21;
background: linear-gradient(135deg, #1cdf21, #1CDFA3);

Monochromatic scale

Palettes built from #1cdf21

Shades — darker

Tints — lighter

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.

#1cdf21 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.

#1cdf21, answered

What color is #1cdf21?

#1cdf21 is a balanced electric green, closest to Lime Green (ΔE2000 4.6). It sits at 122° on the hue wheel with 78% saturation and 49% lightness, which reads as cool.

What is the RGB value of #1cdf21?

rgb(28, 223, 33) — 28 red, 223 green and 33 blue out of 255, or 11% / 87.5% / 12.9% by channel.

Is #1cdf21 a light or a dark color?

It is a light color. Relative luminance is 0.5313 and perceived brightness is 67%, so black text on it reaches 11.63:1.

Should I use black or white text on #1cdf21?

Black. It scores 11.63:1 against #1cdf21, versus 1.81:1 for white — AAA at any size.

What is the complementary color of #1cdf21?

#DF1CDA sits directly opposite on the wheel. Softer options are the split-complements #821CDF and #DF1C79, which give the same contrast with far less vibration.

What colors go well with #1cdf21?

For interface work: #F4FAF4 as the surface, #C0EDC1 for borders, #4B9B4D for secondary text, #B617E4 as an accent and #0E7111 for hover and pressed states. For a palette, the analogous pair #79DF1C and #1CDF82 stays calm, while #DF1CDA is the loudest partner.

What is #1cdf21 in CMYK for printing?

cmyk(87%, 0%, 85%, 13%). 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 #1cdf21 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 #5FDF1C; nudged cooler, #19E168.

Work with #1cdf21 in the Color Lab