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#129ccc

a dark, electric cyan · cool · closest name: Deep Sky Blue

RGB
18, 156, 204
HSL
196°, 84%, 44%
CMYK
91, 24, 0, 20
Luminance
0.2827

At a glance

Every number on this page in one read: what #129ccc is made of, how bright it looks, and which way it leans.

Hex
#129ccc
Hue
196°
cyan
Saturation
84%
electric
Lightness
44%
dark
Brightness
80%
HSV value
Perceived
54%
weighted brightness
Luminance
0.2827
WCAG relative
Temperature
Cool
94/100 cool
Color family
Cyan
Tone
Electric
Best ink
Black
6.65:1
Closest name
Deep Sky Blue
ΔE2000 10.4
Where it sits
Hue196° of 360°
Saturation84%
Lightness44%
Temperature
Warm ← → Cool94% 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#129ccc
RGBrgb(18, 156, 204)
HSLhsl(196, 84%, 44%)
CMYKcmyk(91%, 24%, 0%, 20%)
LABlab(60.1 -16.4 -34.0)
LCHlch(60.1 37.7 244.2)
OKLCHoklch(0.649 0.126 229.7)
Decimal1219788
Display P3color(display-p3 0.071 0.612 0.800)

Copy-ready code

/* CSS */
color: #129ccc;
background-color: #129ccc;
/* Tailwind (arbitrary) */
class="text-[#129ccc] bg-[#129ccc]"
/* SCSS */
$brand: #129ccc;
/* SwiftUI */
Color(red: 0.071, green: 0.612, blue: 0.800)
/* Android */
Color.parseColor("#129ccc")
/* Flutter */
Color(0xFF129CCC)
/* Python / OpenCV (BGR) */
(204, 156, 18)

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 #129ccc · 6.65:1
Use #000000AA at every size, AAA for large text only.
Aa
White text · 3.16:1
AA fail · AA large pass · AAA fail
Aa
Black text · 6.65:1 · recommended
AA pass · AA large pass · AAA fail
Reading the other direction: #129ccc as text scores 3.16:1 on white and 6.65:1 on black.

Accessibility — WCAG contrast

Aa
#129ccc on white: 3.16:1
AA ✗ fail · AA-large · AAA
Aa
#129ccc on black: 6.65:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #839ACE
deuteranopia · #6C8ACB
tritanopia · #00A9AC

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #129ccc 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.

#F2FAFC
#E6F5FA
#C5EAF6
#98DEF6
#64CDF1
#31BCED
#14ACE1
#129ccc
#0D7396
#0E546C
#093544
Base = 700Lightest = 50 · #F2FAFCDarkest = 950 · #093544
:root {
  --brand-50: #F2FAFC;
  --brand-100: #E6F5FA;
  --brand-200: #C5EAF6;
  --brand-300: #98DEF6;
  --brand-400: #64CDF1;
  --brand-500: #31BCED;
  --brand-600: #14ACE1;
  --brand-700: #129ccc;
  --brand-800: #0D7396;
  --brand-900: #0E546C;
  --brand-950: #093544;
  --brand: #129ccc;
  --brand-ink: #000000;
}

Colors that work with #129ccc

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#F4F9FA
Tinted page background
Border#C0E1ED
Hairlines and dividers
Muted text#4B869B
Captions on the surface
Accent#D00F0E
Second voice, not a rival
Dark variant#0A5A75
Hover, pressed, headers
Light variant#E8F7FD
Selected rows, tints
Dark surface#142024
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 #129ccc

Derived from its contrast, chroma and lightness — not from taste.

Works well for
  • Headings from 24px up on white
  • 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
  • Small text on white — under 4.5:1
  • Full-page backgrounds — tiring over long sessions
  • Black 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#CC4212
Analogous left#12CC9F
Analogous right#123FCC
Split-complement 1#CC123F
Split-complement 2#CC9F12
Triadic 1#CC129C
Triadic 2#9CCC12
Tetradic#9F12CC

RGB percentages

Red7.1%
Green61.2%
Blue80.0%

CMYK percentages

Cyan91.2%
Magenta23.5%
Yellow0.0%
Key (black)20.0%

Color previews

#129ccc text on a black background

contrast 6.65:1

Card sample

#129ccc text on a white background

contrast 3.16:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #129ccc;
Background color
Panel with #129ccc background
background-color: #129ccc;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #129ccc;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(18, 156, 204, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(18, 156, 204, 0.45);
Border & gradient
Gradient panel
border: 3px solid #129ccc;
background: linear-gradient(135deg, #129ccc, #1220CC);

Monochromatic scale

Palettes built from #129ccc

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.

#129ccc 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.

#129ccc, answered

What color is #129ccc?

#129ccc is a dark electric cyan, closest to Deep Sky Blue (ΔE2000 10.4). It sits at 196° on the hue wheel with 84% saturation and 44% lightness, which reads as cool.

What is the RGB value of #129ccc?

rgb(18, 156, 204) — 18 red, 156 green and 204 blue out of 255, or 7.1% / 61.2% / 80% by channel.

Is #129ccc a light or a dark color?

It is a mid-tone. Relative luminance is 0.2827 and perceived brightness is 54%, so black text on it reaches 6.65:1.

Should I use black or white text on #129ccc?

Black. It scores 6.65:1 against #129ccc, versus 3.16:1 for white — AA at any size.

What is the complementary color of #129ccc?

#CC4212 sits directly opposite on the wheel. Softer options are the split-complements #CC123F and #CC9F12, which give the same contrast with far less vibration.

What colors go well with #129ccc?

For interface work: #F4F9FA as the surface, #C0E1ED for borders, #4B869B for secondary text, #D00F0E as an accent and #0A5A75 for hover and pressed states. For a palette, the analogous pair #12CC9F and #123FCC stays calm, while #CC4212 is the loudest partner.

What is #129ccc in CMYK for printing?

cmyk(91%, 24%, 0%, 20%). 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 #129ccc warm or cool?

Cool — it scores 94 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #12CCB8; nudged cooler, #1083CE.

Work with #129ccc in the Color Lab