Skip to content

#63d8eb

a light, electric cyan · cool · closest name: Sky Blue

RGB
99, 216, 235
HSL
188°, 77%, 66%
CMYK
58, 8, 0, 8
Luminance
0.5776

At a glance

Every number on this page in one read: what #63d8eb is made of, how bright it looks, and which way it leans.

Hex
#63d8eb
Hue
188°
cyan
Saturation
77%
electric
Lightness
66%
light
Brightness
92%
HSV value
Perceived
75%
weighted brightness
Luminance
0.5776
WCAG relative
Temperature
Cool
91/100 cool
Color family
Cyan
Tone
Electric
Best ink
Black
12.55:1
Closest name
Sky Blue
ΔE2000 7.4
Where it sits
Hue188° of 360°
Saturation77%
Lightness66%
Temperature
Warm ← → Cool91% 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#63d8eb
RGBrgb(99, 216, 235)
HSLhsl(188, 77%, 66%)
CMYKcmyk(58%, 8%, 0%, 8%)
LABlab(80.6 -27.6 -19.3)
LCHlch(80.6 33.7 215.0)
OKLCHoklch(0.822 0.108 209.6)
Decimal6543595
Display P3color(display-p3 0.388 0.847 0.922)

Copy-ready code

/* CSS */
color: #63d8eb;
background-color: #63d8eb;
/* Tailwind (arbitrary) */
class="text-[#63d8eb] bg-[#63d8eb]"
/* SCSS */
$brand: #63d8eb;
/* SwiftUI */
Color(red: 0.388, green: 0.847, blue: 0.922)
/* Android */
Color.parseColor("#63d8eb")
/* Flutter */
Color(0xFF63D8EB)
/* Python / OpenCV (BGR) */
(235, 216, 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 #63d8eb · 12.55:1
Use #000000AAA at every size.
Aa
White text · 1.67:1
AA fail · AA large fail · AAA fail
Aa
Black text · 12.55:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #63d8eb as text scores 1.67:1 on white and 12.55:1 on black.

Accessibility — WCAG contrast

Aa
#63d8eb on white: 1.67:1
AA ✗ fail · AA-large · AAA
Aa
#63d8eb on black: 12.55:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #C7D1EC
deuteranopia · #B2C1EB
tritanopia · #00E1DE

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #63d8eb 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.

#F3FBFC
#E6F6F9
#C7EEF4
#9CE6F2
#63d8eb
#38CDE6
#1CBFD9
#179FB5
#137F91
#125D69
#0B3A41
Base = 400Lightest = 50 · #F3FBFCDarkest = 950 · #0B3A41
:root {
  --brand-50: #F3FBFC;
  --brand-100: #E6F6F9;
  --brand-200: #C7EEF4;
  --brand-300: #9CE6F2;
  --brand-400: #63d8eb;
  --brand-500: #38CDE6;
  --brand-600: #1CBFD9;
  --brand-700: #179FB5;
  --brand-800: #137F91;
  --brand-900: #125D69;
  --brand-950: #0B3A41;
  --brand: #63d8eb;
  --brand-ink: #000000;
}

Colors that work with #63d8eb

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#F4FAFA
Tinted page background
Border#C0E6ED
Hairlines and dividers
Muted text#4B909B
Captions on the surface
Accent#EF606F
Second voice, not a rival
Dark variant#0E6371
Hover, pressed, headers
Light variant#E8F9FC
Selected rows, tints
Dark surface#142224
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 #63d8eb

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
  • Card and section backgrounds
  • 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
  • White text placed on it
  • 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#EB7663
Analogous left#63EBBA
Analogous right#6394EB
Split-complement 1#EB6394
Split-complement 2#EBBA63
Triadic 1#EB63D8
Triadic 2#D8EB63
Tetradic#BA63EB

RGB percentages

Red38.8%
Green84.7%
Blue92.2%

CMYK percentages

Cyan57.9%
Magenta8.1%
Yellow0.0%
Key (black)7.8%

Color previews

#63d8eb text on a black background

contrast 12.55:1

Card sample

#63d8eb text on a white background

contrast 1.67:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #63d8eb;
Background color
Panel with #63d8eb background
background-color: #63d8eb;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #63d8eb;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(99, 216, 235, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(99, 216, 235, 0.45);
Border & gradient
Gradient panel
border: 3px solid #63d8eb;
background: linear-gradient(135deg, #63d8eb, #637DEB);

Monochromatic scale

Palettes built from #63d8eb

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.

#63d8eb 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
SurfacesBadgesHighlightsEmpty states
Print note

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

#63d8eb, answered

What color is #63d8eb?

#63d8eb is a light electric cyan, closest to Sky Blue (ΔE2000 7.4). It sits at 188° on the hue wheel with 77% saturation and 66% lightness, which reads as cool.

What is the RGB value of #63d8eb?

rgb(99, 216, 235) — 99 red, 216 green and 235 blue out of 255, or 38.8% / 84.7% / 92.2% by channel.

Is #63d8eb a light or a dark color?

It is a light color. Relative luminance is 0.5776 and perceived brightness is 75%, so black text on it reaches 12.55:1.

Should I use black or white text on #63d8eb?

Black. It scores 12.55:1 against #63d8eb, versus 1.67:1 for white — AAA at any size.

What is the complementary color of #63d8eb?

#EB7663 sits directly opposite on the wheel. Softer options are the split-complements #EB6394 and #EBBA63, which give the same contrast with far less vibration.

What colors go well with #63d8eb?

For interface work: #F4FAFA as the surface, #C0E6ED for borders, #4B909B for secondary text, #EF606F as an accent and #0E6371 for hover and pressed states. For a palette, the analogous pair #63EBBA and #6394EB stays calm, while #EB7663 is the loudest partner.

What is #63d8eb in CMYK for printing?

cmyk(58%, 8%, 0%, 8%). 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 #63d8eb warm or cool?

Cool — it scores 91 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #63EBCC; nudged cooler, #61B9ED.

Work with #63d8eb in the Color Lab