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#39cf09

a dark, electric green · neutral · closest name: Lime Green

RGB
57, 207, 9
HSL
106°, 92%, 42%
CMYK
73, 0, 96, 19
Luminance
0.4552

At a glance

Every number on this page in one read: what #39cf09 is made of, how bright it looks, and which way it leans.

Hex
#39cf09
Hue
106°
green
Saturation
92%
electric
Lightness
42%
dark
Brightness
81%
HSV value
Perceived
63%
weighted brightness
Luminance
0.4552
WCAG relative
Temperature
Neutral
56/100 cool
Color family
Green
Tone
Electric
Best ink
Black
10.10:1
Closest name
Lime Green
ΔE2000 2.5
Where it sits
Hue106° of 360°
Saturation92%
Lightness42%
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.

Every format

HEX#39cf09
RGBrgb(57, 207, 9)
HSLhsl(106, 92%, 42%)
CMYKcmyk(73%, 0%, 96%, 19%)
LABlab(73.2 -68.4 70.9)
LCHlch(73.2 98.5 134.0)
OKLCHoklch(0.747 0.242 140.7)
Decimal3788553
Display P3color(display-p3 0.224 0.812 0.035)

Copy-ready code

/* CSS */
color: #39cf09;
background-color: #39cf09;
/* Tailwind (arbitrary) */
class="text-[#39cf09] bg-[#39cf09]"
/* SCSS */
$brand: #39cf09;
/* SwiftUI */
Color(red: 0.224, green: 0.812, blue: 0.035)
/* Android */
Color.parseColor("#39cf09")
/* Flutter */
Color(0xFF39CF09)
/* Python / OpenCV (BGR) */
(9, 207, 57)

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 #39cf09 · 10.10:1
Use #000000AAA at every size.
Aa
White text · 2.08:1
AA fail · AA large fail · AAA fail
Aa
Black text · 10.10:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #39cf09 as text scores 2.08:1 on white and 10.10:1 on black.

Accessibility — WCAG contrast

Aa
#39cf09 on white: 2.08:1
AA ✗ fail · AA-large · AAA
Aa
#39cf09 on black: 10.10:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #D5BB00
deuteranopia · #C4AF2F
tritanopia · #0AC8B0

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #39cf09 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.

#F4FDF2
#EAFBE4
#D0F9C3
#ACFA93
#83F85E
#5AF628
#40EB0A
#39cf09
#2B9C07
#23710A
#164706
Base = 700Lightest = 50 · #F4FDF2Darkest = 950 · #164706
:root {
  --brand-50: #F4FDF2;
  --brand-100: #EAFBE4;
  --brand-200: #D0F9C3;
  --brand-300: #ACFA93;
  --brand-400: #83F85E;
  --brand-500: #5AF628;
  --brand-600: #40EB0A;
  --brand-700: #39cf09;
  --brand-800: #2B9C07;
  --brand-900: #23710A;
  --brand-950: #164706;
  --brand: #39cf09;
  --brand-ink: #000000;
}

Colors that work with #39cf09

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#6E05D4
Second voice, not a rival
Dark variant#227A05
Hover, pressed, headers
Light variant#ECFEE7
Selected rows, tints
Dark surface#182414
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 #39cf09

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
  • 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#9F09CF
Analogous left#9CCF09
Analogous right#09CF3C
Split-complement 1#3C09CF
Split-complement 2#CF099C
Triadic 1#0939CF
Triadic 2#CF0939
Tetradic#099CCF

RGB percentages

Red22.4%
Green81.2%
Blue3.5%

CMYK percentages

Cyan72.5%
Magenta0.0%
Yellow95.7%
Key (black)18.8%

Color previews

#39cf09 text on a black background

contrast 10.10:1

Card sample

#39cf09 text on a white background

contrast 2.08:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #39cf09;
Background color
Panel with #39cf09 background
background-color: #39cf09;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #39cf09;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(57, 207, 9, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(57, 207, 9, 0.45);
Border & gradient
Gradient panel
border: 3px solid #39cf09;
background: linear-gradient(135deg, #39cf09, #09CF5D);

Monochromatic scale

Palettes built from #39cf09

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.

#39cf09 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.

#39cf09, answered

What color is #39cf09?

#39cf09 is a dark electric green, closest to Lime Green (ΔE2000 2.5). It sits at 106° on the hue wheel with 92% saturation and 42% lightness, which reads as neutral.

What is the RGB value of #39cf09?

rgb(57, 207, 9) — 57 red, 207 green and 9 blue out of 255, or 22.4% / 81.2% / 3.5% by channel.

Is #39cf09 a light or a dark color?

It is a mid-tone. Relative luminance is 0.4552 and perceived brightness is 63%, so black text on it reaches 10.10:1.

Should I use black or white text on #39cf09?

Black. It scores 10.10:1 against #39cf09, versus 2.08:1 for white — AAA at any size.

What is the complementary color of #39cf09?

#9F09CF sits directly opposite on the wheel. Softer options are the split-complements #3C09CF and #CF099C, which give the same contrast with far less vibration.

What colors go well with #39cf09?

For interface work: #F6FAF4 as the surface, #CBEDC0 for borders, #5E9B4B for secondary text, #6E05D4 as an accent and #227A05 for hover and pressed states. For a palette, the analogous pair #9CCF09 and #09CF3C stays calm, while #9F09CF is the loudest partner.

What is #39cf09 in CMYK for printing?

cmyk(73%, 0%, 96%, 19%). 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 #39cf09 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 #82CF09; nudged cooler, #07D120.

Work with #39cf09 in the Color Lab