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#3ffdcf

a balanced, electric cyan · cool · closest name: Aqua Marine

RGB
63, 253, 207
HSL
166°, 98%, 62%
CMYK
75, 0, 18, 1
Luminance
0.7581

At a glance

Every number on this page in one read: what #3ffdcf is made of, how bright it looks, and which way it leans.

Hex
#3ffdcf
Hue
166°
cyan
Saturation
98%
electric
Lightness
62%
balanced
Brightness
99%
HSV value
Perceived
82%
weighted brightness
Luminance
0.7581
WCAG relative
Temperature
Cool
81/100 cool
Color family
Cyan
Tone
Electric
Best ink
Black
16.16:1
Closest name
Aqua Marine
ΔE2000 3.8
Where it sits
Hue166° of 360°
Saturation98%
Lightness62%
Temperature
Warm ← → Cool81% 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#3ffdcf
RGBrgb(63, 253, 207)
HSLhsl(166, 98%, 62%)
CMYKcmyk(75%, 0%, 18%, 1%)
LABlab(89.8 -56.5 8.8)
LCHlch(89.8 57.2 171.1)
OKLCHoklch(0.892 0.160 171.9)
Decimal4193743
Display P3color(display-p3 0.247 0.992 0.812)

Copy-ready code

/* CSS */
color: #3ffdcf;
background-color: #3ffdcf;
/* Tailwind (arbitrary) */
class="text-[#3ffdcf] bg-[#3ffdcf]"
/* SCSS */
$brand: #3ffdcf;
/* SwiftUI */
Color(red: 0.247, green: 0.992, blue: 0.812)
/* Android */
Color.parseColor("#3ffdcf")
/* Flutter */
Color(0xFF3FFDCF)
/* Python / OpenCV (BGR) */
(207, 253, 63)

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 #3ffdcf · 16.16:1
Use #000000AAA at every size.
Aa
White text · 1.30:1
AA fail · AA large fail · AAA fail
Aa
Black text · 16.16:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #3ffdcf as text scores 1.30:1 on white and 16.16:1 on black.

Accessibility — WCAG contrast

Aa
#3ffdcf on white: 1.30:1
AA ✗ fail · AA-large · AAA
Aa
#3ffdcf on black: 16.16:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #F5ECCD
deuteranopia · #DDDAD2
tritanopia · #00FFF0

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #3ffdcf is pinned to step 400; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F1FDFB
#E3FCF6
#C1FBED
#90FEE3
#3ffdcf
#21FDC8
#03F2B8
#02CA9A
#02A17B
#06745A
#044938
Base = 400Lightest = 50 · #F1FDFBDarkest = 950 · #044938
:root {
  --brand-50: #F1FDFB;
  --brand-100: #E3FCF6;
  --brand-200: #C1FBED;
  --brand-300: #90FEE3;
  --brand-400: #3ffdcf;
  --brand-500: #21FDC8;
  --brand-600: #03F2B8;
  --brand-700: #02CA9A;
  --brand-800: #02A17B;
  --brand-900: #06745A;
  --brand-950: #044938;
  --brand: #3ffdcf;
  --brand-ink: #000000;
}

Colors that work with #3ffdcf

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#F4FAF9
Tinted page background
Border#C0EDE2
Hairlines and dividers
Muted text#4B9B88
Captions on the surface
Accent#FF3D9C
Second voice, not a rival
Dark variant#017E60
Hover, pressed, headers
Light variant#E6FFF9
Selected rows, tints
Dark surface#142420
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 #3ffdcf

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
  • Thin strokes and 1px borders — they disappear on light UI
  • 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#FD3F6D
Analogous left#3FFD70
Analogous right#3FCCFD
Split-complement 1#FD3FCC
Split-complement 2#FD703F
Triadic 1#CF3FFD
Triadic 2#FDCF3F
Tetradic#703FFD

RGB percentages

Red24.7%
Green99.2%
Blue81.2%

CMYK percentages

Cyan75.1%
Magenta0.0%
Yellow18.2%
Key (black)0.8%

Color previews

#3ffdcf text on a black background

contrast 16.16:1

Card sample

#3ffdcf text on a white background

contrast 1.30:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #3ffdcf;
Background color
Panel with #3ffdcf background
background-color: #3ffdcf;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #3ffdcf;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(63, 253, 207, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(63, 253, 207, 0.45);
Border & gradient
Gradient panel
border: 3px solid #3ffdcf;
background: linear-gradient(135deg, #3ffdcf, #3FACFD);

Monochromatic scale

Palettes built from #3ffdcf

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.

#3ffdcf in the real world

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

Industries
TechnologyTravelHealthcareMedia
Common UI roles
ButtonsLinksFocus statesCharts
Print note

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

#3ffdcf, answered

What color is #3ffdcf?

#3ffdcf is a balanced electric cyan, closest to Aqua Marine (ΔE2000 3.8). It sits at 166° on the hue wheel with 98% saturation and 62% lightness, which reads as cool.

What is the RGB value of #3ffdcf?

rgb(63, 253, 207) — 63 red, 253 green and 207 blue out of 255, or 24.7% / 99.2% / 81.2% by channel.

Is #3ffdcf a light or a dark color?

It is a light color. Relative luminance is 0.7581 and perceived brightness is 82%, so black text on it reaches 16.16:1.

Should I use black or white text on #3ffdcf?

Black. It scores 16.16:1 against #3ffdcf, versus 1.30:1 for white — AAA at any size.

What is the complementary color of #3ffdcf?

#FD3F6D sits directly opposite on the wheel. Softer options are the split-complements #FD3FCC and #FD703F, which give the same contrast with far less vibration.

What colors go well with #3ffdcf?

For interface work: #F4FAF9 as the surface, #C0EDE2 for borders, #4B9B88 for secondary text, #FF3D9C as an accent and #017E60 for hover and pressed states. For a palette, the analogous pair #3FFD70 and #3FCCFD stays calm, while #FD3F6D is the loudest partner.

What is #3ffdcf in CMYK for printing?

cmyk(75%, 0%, 18%, 1%). 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 #3ffdcf warm or cool?

Cool — it scores 81 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #3FFD8A; nudged cooler, #3DE7FF.

Work with #3ffdcf in the Color Lab