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#63cfba

a balanced, vivid cyan · cool · closest name: Medium Aqua Marine

RGB
99, 207, 186
HSL
168°, 53%, 60%
CMYK
52, 0, 10, 19
Luminance
0.5082

At a glance

Every number on this page in one read: what #63cfba is made of, how bright it looks, and which way it leans.

Hex
#63cfba
Hue
168°
cyan
Saturation
53%
vivid
Lightness
60%
balanced
Brightness
81%
HSV value
Perceived
70%
weighted brightness
Luminance
0.5082
WCAG relative
Temperature
Cool
83/100 cool
Color family
Cyan
Tone
Vivid
Best ink
Black
11.16:1
Closest name
Medium Aqua Marine
ΔE2000 4.6
Where it sits
Hue168° of 360°
Saturation53%
Lightness60%
Temperature
Warm ← → Cool83% 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#63cfba
RGBrgb(99, 207, 186)
HSLhsl(168, 53%, 60%)
CMYKcmyk(52%, 0%, 10%, 19%)
LABlab(76.6 -36.2 1.0)
LCHlch(76.6 36.2 178.5)
OKLCHoklch(0.785 0.105 178.9)
Decimal6541242
Display P3color(display-p3 0.388 0.812 0.729)

Copy-ready code

/* CSS */
color: #63cfba;
background-color: #63cfba;
/* Tailwind (arbitrary) */
class="text-[#63cfba] bg-[#63cfba]"
/* SCSS */
$brand: #63cfba;
/* SwiftUI */
Color(red: 0.388, green: 0.812, blue: 0.729)
/* Android */
Color.parseColor("#63cfba")
/* Flutter */
Color(0xFF63CFBA)
/* Python / OpenCV (BGR) */
(186, 207, 99)

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 #63cfba · 11.16:1
Use #000000AAA at every size.
Aa
White text · 1.88:1
AA fail · AA large fail · AAA fail
Aa
Black text · 11.16:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #63cfba as text scores 1.88:1 on white and 11.16:1 on black.

Accessibility — WCAG contrast

Aa
#63cfba on white: 1.88:1
AA ✗ fail · AA-large · AAA
Aa
#63cfba on black: 11.16:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #C8C4B9
deuteranopia · #B7B8BC
tritanopia · #28D2C9

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #63cfba 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.

#F4FBF9
#E9F6F4
#CEEDE7
#A9E5D9
#7ED7C6
#63cfba
#3ABBA2
#309C87
#267D6C
#1F5B4F
#143932
Base = 500Lightest = 50 · #F4FBF9Darkest = 950 · #143932
:root {
  --brand-50: #F4FBF9;
  --brand-100: #E9F6F4;
  --brand-200: #CEEDE7;
  --brand-300: #A9E5D9;
  --brand-400: #7ED7C6;
  --brand-500: #63cfba;
  --brand-600: #3ABBA2;
  --brand-700: #309C87;
  --brand-800: #267D6C;
  --brand-900: #1F5B4F;
  --brand-950: #143932;
  --brand: #63cfba;
  --brand-ink: #000000;
}

Colors that work with #63cfba

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#C1ECE3
Hairlines and dividers
Muted text#4B9B8B
Captions on the surface
Accent#D35F93
Second voice, not a rival
Dark variant#1E6154
Hover, pressed, headers
Light variant#ECF9F6
Selected rows, tints
Dark surface#142421
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 #63cfba

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#CF6378
Analogous left#63CF84
Analogous right#63AECF
Split-complement 1#CF63AE
Split-complement 2#CF8463
Triadic 1#BA63CF
Triadic 2#CFBA63
Tetradic#8463CF

RGB percentages

Red38.8%
Green81.2%
Blue72.9%

CMYK percentages

Cyan52.2%
Magenta0.0%
Yellow10.1%
Key (black)18.8%

Color previews

#63cfba text on a black background

contrast 11.16:1

Card sample

#63cfba text on a white background

contrast 1.88:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #63cfba;
Background color
Panel with #63cfba background
background-color: #63cfba;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #63cfba;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(99, 207, 186, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(99, 207, 186, 0.45);
Border & gradient
Gradient panel
border: 3px solid #63cfba;
background: linear-gradient(135deg, #63cfba, #639CCF);

Monochromatic scale

Palettes built from #63cfba

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.

#63cfba 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

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

#63cfba, answered

What color is #63cfba?

#63cfba is a balanced vivid cyan, closest to Medium Aqua Marine (ΔE2000 4.6). It sits at 168° on the hue wheel with 53% saturation and 60% lightness, which reads as cool.

What is the RGB value of #63cfba?

rgb(99, 207, 186) — 99 red, 207 green and 186 blue out of 255, or 38.8% / 81.2% / 72.9% by channel.

Is #63cfba a light or a dark color?

It is a light color. Relative luminance is 0.5082 and perceived brightness is 70%, so black text on it reaches 11.16:1.

Should I use black or white text on #63cfba?

Black. It scores 11.16:1 against #63cfba, versus 1.88:1 for white — AAA at any size.

What is the complementary color of #63cfba?

#CF6378 sits directly opposite on the wheel. Softer options are the split-complements #CF63AE and #CF8463, which give the same contrast with far less vibration.

What colors go well with #63cfba?

For interface work: #F4FAF9 as the surface, #C1ECE3 for borders, #4B9B8B for secondary text, #D35F93 as an accent and #1E6154 for hover and pressed states. For a palette, the analogous pair #63CF84 and #63AECF stays calm, while #CF6378 is the loudest partner.

What is #63cfba in CMYK for printing?

cmyk(52%, 0%, 10%, 19%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #63cfba warm or cool?

Cool — it scores 83 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #63CF92; nudged cooler, #61BED1.

Work with #63cfba in the Color Lab