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#33cdf9

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

RGB
51, 205, 249
HSL
193°, 94%, 59%
CMYK
80, 18, 0, 2
Luminance
0.5121

At a glance

Every number on this page in one read: what #33cdf9 is made of, how bright it looks, and which way it leans.

Hex
#33cdf9
Hue
193°
cyan
Saturation
94%
electric
Lightness
59%
balanced
Brightness
98%
HSV value
Perceived
71%
weighted brightness
Luminance
0.5121
WCAG relative
Temperature
Cool
93/100 cool
Color family
Cyan
Tone
Electric
Best ink
Black
11.24:1
Closest name
Deep Sky Blue
ΔE2000 6.2
Where it sits
Hue193° of 360°
Saturation94%
Lightness59%
Temperature
Warm ← → Cool93% 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#33cdf9
RGBrgb(51, 205, 249)
HSLhsl(193, 94%, 59%)
CMYKcmyk(80%, 18%, 0%, 2%)
LABlab(76.8 -24.4 -32.7)
LCHlch(76.8 40.8 233.2)
OKLCHoklch(0.790 0.136 222.5)
Decimal3395065
Display P3color(display-p3 0.200 0.804 0.976)

Copy-ready code

/* CSS */
color: #33cdf9;
background-color: #33cdf9;
/* Tailwind (arbitrary) */
class="text-[#33cdf9] bg-[#33cdf9]"
/* SCSS */
$brand: #33cdf9;
/* SwiftUI */
Color(red: 0.200, green: 0.804, blue: 0.976)
/* Android */
Color.parseColor("#33cdf9")
/* Flutter */
Color(0xFF33CDF9)
/* Python / OpenCV (BGR) */
(249, 205, 51)

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 #33cdf9 · 11.24:1
Use #000000AAA at every size.
Aa
White text · 1.87:1
AA fail · AA large fail · AAA fail
Aa
Black text · 11.24:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #33cdf9 as text scores 1.87:1 on white and 11.24:1 on black.

Accessibility — WCAG contrast

Aa
#33cdf9 on white: 1.87:1
AA ✗ fail · AA-large · AAA
Aa
#33cdf9 on black: 11.24:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #B3C8FB
deuteranopia · #9AB5F9
tritanopia · #00DBDB

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #33cdf9 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.

#F2FBFD
#E4F6FB
#C2EDFA
#92E4FC
#5BD7FA
#33cdf9
#07BBEE
#069CC6
#057C9F
#085B72
#053947
Base = 500Lightest = 50 · #F2FBFDDarkest = 950 · #053947
:root {
  --brand-50: #F2FBFD;
  --brand-100: #E4F6FB;
  --brand-200: #C2EDFA;
  --brand-300: #92E4FC;
  --brand-400: #5BD7FA;
  --brand-500: #33cdf9;
  --brand-600: #07BBEE;
  --brand-700: #069CC6;
  --brand-800: #057C9F;
  --brand-900: #085B72;
  --brand-950: #053947;
  --brand: #33cdf9;
  --brand-ink: #000000;
}

Colors that work with #33cdf9

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#C0E3ED
Hairlines and dividers
Muted text#4B899B
Captions on the surface
Accent#FD2F35
Second voice, not a rival
Dark variant#04617C
Hover, pressed, headers
Light variant#E6F9FE
Selected rows, tints
Dark surface#142124
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 #33cdf9

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#F95F33
Analogous left#33F9C2
Analogous right#336AF9
Split-complement 1#F9336A
Split-complement 2#F9C233
Triadic 1#F933CD
Triadic 2#CDF933
Tetradic#C233F9

RGB percentages

Red20.0%
Green80.4%
Blue97.6%

CMYK percentages

Cyan79.5%
Magenta17.7%
Yellow0.0%
Key (black)2.4%

Color previews

#33cdf9 text on a black background

contrast 11.24:1

Card sample

#33cdf9 text on a white background

contrast 1.87:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #33cdf9;
Background color
Panel with #33cdf9 background
background-color: #33cdf9;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #33cdf9;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(51, 205, 249, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(51, 205, 249, 0.45);
Border & gradient
Gradient panel
border: 3px solid #33cdf9;
background: linear-gradient(135deg, #33cdf9, #3349F9);

Monochromatic scale

Palettes built from #33cdf9

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.

#33cdf9 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.

#33cdf9, answered

What color is #33cdf9?

#33cdf9 is a balanced electric cyan, closest to Deep Sky Blue (ΔE2000 6.2). It sits at 193° on the hue wheel with 94% saturation and 59% lightness, which reads as cool.

What is the RGB value of #33cdf9?

rgb(51, 205, 249) — 51 red, 205 green and 249 blue out of 255, or 20% / 80.4% / 97.6% by channel.

Is #33cdf9 a light or a dark color?

It is a light color. Relative luminance is 0.5121 and perceived brightness is 71%, so black text on it reaches 11.24:1.

Should I use black or white text on #33cdf9?

Black. It scores 11.24:1 against #33cdf9, versus 1.87:1 for white — AAA at any size.

What is the complementary color of #33cdf9?

#F95F33 sits directly opposite on the wheel. Softer options are the split-complements #F9336A and #F9C233, which give the same contrast with far less vibration.

What colors go well with #33cdf9?

For interface work: #F4F9FA as the surface, #C0E3ED for borders, #4B899B for secondary text, #FD2F35 as an accent and #04617C for hover and pressed states. For a palette, the analogous pair #33F9C2 and #336AF9 stays calm, while #F95F33 is the loudest partner.

What is #33cdf9 in CMYK for printing?

cmyk(80%, 18%, 0%, 2%). 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 #33cdf9 warm or cool?

Cool — it scores 93 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #33F9DC; nudged cooler, #31B0FB.

Work with #33cdf9 in the Color Lab